
==== Front
Infect Med (Beijing)
Infect Med (Beijing)
Infectious Medicine
2097-0684
2772-431X
Elsevier

S2772-431X(24)00037-6
10.1016/j.imj.2024.100123
100123
Case Report
Infectious intracranial aneurysm associated with Lactococcus garvieae: A case report and literature review
Lee Chung-Ho lch101@ha.org.hk
a1⁎
Woo Peter Yat-Ming b
Leung Calvin Ka-Lam b
Li Ronald b
Chan Jenny Kwan-Tsz b
Ng Kwan-Shun a
Tse Cindy Wing-Sze a
a Department of Pathology, Kwong Wah Hospital, Hong Kong Special Administrative Region, China
b Department of Neurosurgery, Kwong Wah Hospital, Hong Kong Special Administrative Region, China
⁎ Corresponding author. lch101@ha.org.hk
1 First author

30 7 2024
9 2024
30 7 2024
3 3 1001239 2 2024
23 3 2024
22 5 2024
© 2024 The Author(s)
2024
https://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Highlights

• Lactococcus garvieae is a known fish pathogen. Its role as an emerging zoonotic pathogen is increasingly recognised as more cases are reported.

• Infective endocarditis (both native and prosthetic valve) accounts for the majority of human L. garvieae infections, but infections of other organ systems and contamination of platelet concentrates have also been reported.

• The risk factors associated with L. garvieae infection include raw fish contact or consumption and underlying gastrointestinal diseases. Exposure to raw fish was found in one-third of the reported cases of L. garvieae infection, while around half of the reported cases had underlying gastrointestinal disorders.

• β-lactams are the drug of choice for infections due to L. garvieae, clindamycin should be avoided as the organism is intrinsically resistant.

• There were two cases of infectious intracranial aneurysm due to L. garvieae infection reported in the literature, but both cases could be attributed to the underlying infective endocarditis. We report the first case of a ruptured infectious intracranial aneurysm in a patient with L. garvieae bacteraemia without concomitant endocarditis.

Lactococcus garvieae is a known fish pathogen associated with numerous aquacultural outbreaks. In humans, L. garvieae primarily causes infective endocarditis, but infections involving other organs have also been reported. We report the first case of ruptured infectious intracranial aneurysm associated with L. garvieae bacteraemia without concomitant infective endocarditis. The diagnosis of a left distal posterior cerebral artery mycotic aneurysm was based on a computed tomography angiogram, catheter angiogram and histopathological examination of the resected aneurysm. Here, we review the literature on human L. garvieae infections and describe the clinical characteristics, risk factors, management and outcomes of the cases identified to date.

Keywords

Lactococcus garvieae
Bacteraemia
Infectious intracranial aneurysm
Mycotic aneurysm
Subarachnoid haemorrhage
Abbreviations

CT computed tomography

IE infective endocarditis

PCA posterior cerebral artery

IIA infectious intracranial aneurysm
==== Body
pmc1 Case report

A 59-year-old man, who had undergone mechanical aortic valve replacement 25 years ago for aortic stenosis, experienced severe acute onset occipital headache for five days associated with dizziness, neck pain and vomiting. There was no history of head injury. The patient was afebrile and conscious upon admission. There was nuchal rigidity but no focal neurological deficit.

His complete blood count was significant for microcytic hypochromic anaemia and neutrophil-predominant leukocytosis. Liver and renal function tests were unremarkable. Blood culture taken on admission was positive for Gram-positive cocci in chains after one day of incubation in the BD BACTEC™ FX blood culture system (Fig. 1A and B). The organism was identified as Lactococcus garvieae by matrix-assisted laser desorption ionization-time of flight mass spectrometry with Bruker Microflex® LT (Bruker Daltonics, Bremen, Germany) and automated biochemical testing system with VITEK 2 (bioMérieux, Marcy l'Etoile, France). The isolate was sensitive to penicillin, ceftriaxone and vancomycin according to the Clinical Laboratory and Standards Institute breakpoints. The minimum inhibitory concentrations of penicillin, ceftriaxone and vancomycin were 0.19 µg/mL, 0.064 µg/mL and 0.5 µg/mL, respectively.Fig. 1 Gram stain of the positive blood culture showing Gram-positive cocci in chains (A). Colony morphology of L. garvieae (B). Gross appearance of the aneurysm (C). Haematoxylin and eosin staining demonstrating the aneurysm wall with mixed neutrophilic and lymphocytic infiltrates, magnification 100×. Inset magnification 400× (D).

Fig 1

Non-contrast computed tomography (CT) of the brain showed acute subarachnoid haemorrhage in the left parieto-occipital region (Fig. 2A). A CT angiogram detected a 12 mm distal posterior cerebral artery (PCA) fusiform aneurysm at the praecuneus. Three additional sets of blood culture from separate sites were all positive for L. garvieae after one day of incubation. The patient was managed with intravenous ceftriaxone (1 g Q12H), which resulted in clearance of the bacteraemia.. A transthoracic and transoesophageal echocardiogram revealed no evidence of infective endocarditis (IE). There were also no evidence of other embolic or immunological phenomena.Fig. 2 Axial non-contrast-enhanced CT head scan revealing subarachnoid haemorrhage in the left parieto-occipital region (A). Catheter angiogram after two-weeks of intravenous antibiotics demonstrating an enlarged left distal posterior cerebral artery aneurysm (B, white arrow, left vertebral artery injection lateral view; C, white arrowhead, AP view 3D reconstruction; D, lateral view 3D reconstruction).

Fig 2

In view of the L. garvieae bacteraemia, history regarding fish exposure was explored. The patient consumed a takeaway assorted sushi and sashimi platter with his family four days prior to the onset of his headache and developed diarrhoea two days afterwards, which subsided before hospitalisation. He had no history of undercooked food intake otherwise. His family members remained asymptomatic.

After two weeks of antibiotics, the patient's headache subsided, and serial CT scans showed resolution of the subarachnoid haemorrhage. However, a catheter angiogram revealed an expansion of the distal PCA aneurysm to a diameter of 14 mm (Fig. 2B–D). In view of the aneurysm's enlargement despite antibiotics, a craniotomy for its resection was performed. Histopathological examination of the aneurysm tissue demonstrated mixed neutrophilic and lymphocytic infiltrates compatible with an infected aneurysm (Fig. 1C and D). The patient was discharged after completing six weeks of ceftriaxone. A screening contrast-enhanced CT of the abdomen and pelvis and colonoscopy were performed. The CT scan was unremarkable, but two tubular adenomas at the caecum and transverse colon were identified by colonoscopy and excised. One year after the subarachnoid haemorrhage, the patient remained well with a modified Rankin score of 1.

2 Discussion

L. garvieae is a Gram-positive, facultatively anaerobic organism appearing as cocci in chains. It is known to cause lactococcosis, an acute septicaemic syndrome affecting multiple marine and freshwater animal species [1,2]. Owing to a high mortality rate of up to 50%, lactococcosis outbreaks can cause significant economic losses in the aquaculture industry. Apart from aquatic organisms, L. garvieae has been isolated from a multitude of foods including milk, cheese, meat and fish products [1]. The potential virulence factors include haemolysin III-related proteins, siderophores, internalin, mucus adhesin and sortase A [1].

The role of L. garvieae as an emerging zoonotic pathogen is increasingly recognised with 57 cases reported. The majority of L. garvieae infections (54.4%, 31/57) are IE (Table 1). For L. garvieae IE, both sexes are affected; the male-to-female ratio of the reported cases is 1.4:1. The median age of affected patients is 68 (interquartile range: 59.0–77.5). Nearly half of the patients affected (48.4%, 15/31) had prosthetic valve IE and fatal infections occurred in five cases (16.1%). All patients were treated with systemic antibiotics and around one-third (11/31) of the patients required valve replacement.Table 1 Published literature on cases of infective endocarditis caused by Lactococcus garvieae.

Table 1Reference	Sex/ Age	Comorbid conditions	Site	Clinical presentation	Fish contact/ consumption	Complications	Treatment	Outcome	
Rösch et al. [7]	M/78	Atrial fibrillation, hypertension, chronic kidney disease, right external carotid artery stenosis, history of stenting of right coronary artery	Prosthetic aortic valve	Fever, exertional dyspnoea, expectoration, aortic systolic murmur	No	Nil	Aortic valve replacement. 6 weeks of penicillin and 2 weeks of gentamicin	Survived	
Zuily et al. [15]	F/64	Atrial fibrillation, chronic hepatitis C with cirrhosis, history of pacemaker implantation	Prosthetic mitral valve	Fever	Yes (consumption of fresh seafood)	Nil	Amoxicillin and gentamicin for 6 weeks	Survived	
Malek . [6]	M/50	Chronic rheumatic heart disease with mitral valve replacement, dislipidaemia, reflux oesophagitis	Native aortic valve	Intracranial haemorrhage, flu-like symptoms	No	Intracranial haemorrhage	Ceftriaxone for 6 weeks and gentamicin for 2 weeks. Aortic valve replacement	Survived	
Ortiz et al. [16]	F/70	None	Native mitral valve	Progressive heart failure	No	Heart failure	Vancomycin for 6 weeks. Mitral valve replacement	Survived	
Ortiz et al. [16]	F/77	Hypertension, chronic lymphocytic leukaemia, colorectal cancer with surgery done	Native aortic and mitral valves	Purpuric lesions, fever, acute renal failure	No	Heart failure	Ampicillin and gentamicin	Died	
Russo et al. [17]	M/63	Type A aortic dissection with grafting of aorta and aortic valve replacement, abdominal aortic aneurysm, mitral insufficiency with repair using autologous pericardium, colonic diverticulosis	Native mitral valve	Fever with chills, pharyngodynia and generalised weakness	Yes (consumption of Italian naturally fermented cheese and fish)	Nil	Vancomycin and gentamicin for 2 weeks, followed by ampicillin for 2 weeks	Survived	
Lim et al. [18]	M/85	Erosive gastritis, aortic valve replacement, history of tricuspid valve infective endocarditis	Native mitral valve	Anorexia, right lower limb cramps, acute urinary retention	No	Embolic stroke causing central post-stroke pain syndrome	Ceftriaxone for 6 weeks	Survived	
Watanabe et al. [12]	F/55	Nil	Native mitral valve	Fever, malaise and myalgia	No	Renal infarction, cerebral infarction, and cerebral mycotic aneurysms	Ceftriaxone and gentamicin	Survived	
Heras et al. [19]	M/68	Hypertension, dyslipidemia, Hodgkin lymphoma in remission, complete atrioventricular block with pacemaker implantation, aortic stenosis with aortic valve replacement	Native mitral valve	Fever	No	Mitral abscess, heart failure	Daptomycin, ampicillin, ceftriaxone and gentamicin	Died	
Hirakawa et al. [20]	F/58	Hypertension, type 2 diabetes mellitus, dyslipidaemia, mitral stenosis with mitral valve replacement	Prosthetic mitral valve	Fever, chills, diaphoresis, erythematous nodules in hands and legs, myalgia and weakness	Yes (Consumption of fish and white cheese, with gingival perforation due to fish bone)	Nil	Vancomycin	Survived	
Tsur et al. [21]	M/76	Aortic stenosis with aortic valve replacement, congestive heart failure, atrial fibrillation, type 2 diabetes mellitus, essential hypertension, oesophageal adenocarcinoma with total oesophagectomy	Prosthetic aortic valve	Fever, constipation	Yes (Consumption of sushi)	Nil	Ceftriaxone and gentamicin	Survived	
González-Bravo et al. [22]	M/78	Essential hypertension, dyslipidaemia, gastroesophageal reflux disease, atrial fibrillation, aortic valve replacement	Prosthetic aortic valve	Fever, chills, altered mental status, malaise, anorexia	Yes (Consumption of raw salmon)	Nil	Ceftriaxone for 6 weeks	Survived	
Rasmussen et al. [23]	M/81	Myocardial infarction with coronary artery bypass grafting, stening of carotid artery, aortic valve replacement, atrial fibrillation, rectal diverticulosis	Native mitral valve, prosthetic aortic valve	Malaise, headache, expressive dysphasia	No	Left fronto-temporal subdural haematoma and left cerebellar hemisphere infarction	Penicillin for 4 weeks and tobramycin for 3 weeks	Survived	
Wilbring et al. [24]	M/55	Tricuspid valve replacment	Prosthetic tricuspid valve	Progressive dyspnoea, fever, chills	Yes (Amateur fish farmer)	Nil	Levofloxacin, amoxicillin-clavulanate for 8 weeks, prosthetic tricuspid valve replacement	Survived	
Fleming et al. [25]	M/68	Type 2 diabetes mellitus, non-Hodgkin lymphoma in remission, aortic valve replacement	Native mitral valve and prosthetic aortic valve	Fever, migratory arthralgia, functional decline, anorexia, fatigue, weight loss	Yes (Consumption of raw fish)	Nil	Vancomycin for 6 weeks	Died	
Lim et al. [26]	M/57	Gallstones, colonic polyps	Native mitral valve	Weight loss, fever, and anaemia	No	Nil	Amoxicillin and gentamicin for 6 weeks. Mitral and aortic valve replacement (no vegetation over aortic valve, but replacment done in view of moderate-to-severe aortic regurgitation)	Survived	
Li et al. [27]	M/41	None	Native mitral valve	Right hemiplegia and slurring of speech	Yes (Working as a chef with frequent raw fish contact)	Acute cerebral infarction over the left middle cerebral artery territory	Penicillin and gentamicin for 30 days, mitral valve replacement	Survived	
Fihman et al. [28]	F/86	Aortic valve replacement, colonic diverticulosis, duodenal ulcer	Prosthetic aortic valve	Fever and right hip pain	No	Nil	Amoxicillin for 7 weeks and gentamicin for 3 weeks	Survived	
Navas et al. [29]	M/64	Type 2 diabetes mellitus, hypertension, chronic obstructive pulmonary disease, mitral valve repair, coronary artery bypass grafting, intracardiac difibrillator insertion	Native aortic valve	Progressive fatigue, weight loss, and anorexia	No	Nil	Vancomycin for 6 weeks. Aortic valve replacement, ascending aorta repair, ICD lead and pacemaker removal	Survived	
Fefer et al. [30]	F/84	Hypertrophic cardiomyopathy, complete heart block with pacemaker insertion, hypothyroidism, immune thrombocytopenic purpura, aortic valve replacement	Native mitral valve	Progressive exertional dyspnoea, generalised weakness, anorexia	No	Ruptured cordae tendinae, pulmonary oedema, haemorrhagic pleural effusion, massive left cerebral haemorrhage	Ceftriaxone. Mitral valve replacement	Died	
Suh et al. [31]	F/75	Mitral stenosis with mitral valve replacment, gastritis	Prosthetic mitral valve and native aortic valve	Progressive heart failure	Yes (Consumption of raw fish)	Pulmonary oedema	Ceftriaxone for 26 days. Mitral and aortic valve replacement	Survived	
Vinh et al. [32]	M/80	Type 2 diabetes mellitus, hypercholesterolaemia, coronary artery disease, malignant colonic polyps with resection done	Native aortic valve	Dypsnoea and epigastric discomfort	No	Congestive heart failure	Ampicillin for more than 6 weeks. Aortic valve replacement	Survived	
Yiu et al. [33]	M/67	Chronic rheumatic heart disease, atrial fibrillation	Native mitral valve	Fever, chills and rigors	Yes (Frequent visits to fish market)	Partial rupture of chordae tendinae	Ampicillin for 6 weeks	Survived	
Bazemore et al. [34]	M/45	Hepatitis C with cirrhosis, aortic root aneurysm with Bentall repair, familial adenomatous polyposis	Prosthetic aortic valve	Symptomatic anaemia, generalised malaise and weakness,	No	Splenic and left renal infarct. Near-complete dehiscence of the valve conduit from the aortic annulus and significant destruction of the aortic annulus with a large pseudoaneurysm	Ceftriaxone for 6 weeks and gentamicin for 2 weeks. Aortic root repair and aortic valve replacement	Survived	
James et al. [35]	F/56	Aortic stenosis with aortic valve replacement	Possible prosthetic aortic valve	Low back pain, rigors, night sweats, anorexia, weight loss	No	Vertebral osteomyelitis	Teicoplanin for 2 months	Survived	
Backes et al. [36]	F/68	Hypertension, alcohol abuse, oesophageal varices, diverticulosis, cirrhosis	Native aortic valve	Fever, malaise, weight loss, epistaxis, haematemesis	No	Nil	Amoxicillin and gentamicin for 6 weeks	Survived	
Clavero et al. [37]	F/72	Type 2 diabetes mellitus, hypertension, end-stage kidney disease, colonic diverticulosis	Native mitral valve	Fever and chills during haemodialysis	No	Multiorgan failure	Vancomycin and gentamicin	Died	
Landeloos et al. [38]	F/82	Atrial fibrillation, hypertension, osteoporosis, history of infective endocarditis with mitral valve replacement, colonic polyp	Prosthetic mitral valve	Fever, anorexia, exertional dyspnoea	Yes (Consumption of fish)	Acute ischaemic stroke of the right occipital lobe	Penicillin for 4 weeks and gentamicin for 2 weeks, followed by amoxicillin for 2 weeks	Survived	
Wang et al. [39]	M/72	Mitral valve prolapse, staghorn stone of the right kidney, gastric ulcer	Native mitral valve	Fever and purpuric leg lesions	Yes (Consumption of raw squid)	Nil	Penicillin for 4 weeks and gentamicin for 2 weeks	Survived	
Makhoul et al. [13]	M/65	Hypertension, hyperlipidemia, atrial fibrillation, bicuspid aortic valve, ascending aortic aneurysm with a history of a Bentall procedure	Prosthetic aortic valve	Headache, dysarthria and vomiting	No	Left middle cerebral artery aneurysm with haemorrhage	Ceftriaxone and gentamicin for 6 weeks	Survived	
Rojas-Velasco et al. [40]	F/60	Chronic rheumatic heart disease with history of mitral, tricuspid and aortic valve replacement, chronic heart failure, diabetes mellitus, hypertension, colonic polyps	Prosthetic aortic valve	Fever	No	Nil	Ceftriaxone	Survived	

L. garvieae has also been reported to cause infections other than IE, including primary bacteraemia, osteoarticular infections, urinary tract infections, meningitis and intra-abdominal infections (Table 2). Interestingly, L. garvieae has been implicated in cases of platelet concentrates contamination, which led to recipient sepsis [[3], [4], [5]]. These case reports suggest the potential role of L. garvieae as an emerging pathogen associated with the contamination of blood products and increased vigilance is warranted.Table 2 Published literature on non-infective endocarditis cases caused by Lactococcus garvieae.

Table 2	Sex/ Age	Comorbid conditions	Clinical syndrome	Site where L. garvieae was isolated	Clinical presentation	Fish contact/ consumption	Complications	Treatment	Outcome	
Sahu et al. [41]	M/86	Anterior cervical hyperostosis	Bacteraemia	Blood	Lethargy, decreased mentation, hypotension	No	Nil	Ampicillin and Ceftazidime	Survived	
Lee et al. [42]	M/77	Diabetes mellitus, hypertension, abdominal aortic aneurysm with endovascular repair	Infective spondylitis	Blood	Back pain	No	No	Cefepime for 1 month then Levofloxacin for 6 months	Survived	
Chan et al. [8]	M/70	Gastritis	Infective spondylodiscitis	Bone biopsy of L3-4	Fever and back pain	Yes (Frequent visits to fish market and intake of raw fish)	No	Ampicillin for 6 weeks	Survived	
Tandel et al. [43]	M/75	Chronic alcoholism	Chronic meningitis	Cerebrospinal fluid	Fever, disorientation, weight loss, fatigue, anorexia	No	No	Ceftriaxone and vancomycin	Survived	
Tariq et al. [44]	M/70	Hypertension, benign prostatic hyperplasia, oesophageal cancer with chemoradiotherapy done	Urinary tract infection	Urine	Fever and confusion	No	No	Amoxicillin-clavulanate for 1 week	Survived	
Wang et al. [39]	M/10	Oesophageal stricture due to alkaline ingestion with repeated dilatation and subcutaneous colon interposition	Septic shock	Blood	Shock, cyanosis and altered consciousness	Yes (Consumption of grilled Tilapia)	Acute kidney injury, disseminated intravascular coagulation	Not mentioned	Died	
Wang et al. [39]	F/56	Small bowel diverticulosis, hypertension, asthma, hyperthyroidism	Small bowel diverticulitis	Blood	Suprapubic pain and fever	No	Nil	Cefazolin and gentamicin for 2 days followed by co-trimoxazole for 5 days	Survived	
Wang et al. [39]	M/47	Traffic accident with left globe rupture and multiple facial lacerations requiring surgery	Jejunal perforation	Ascitic fluid	Fever and abdominal pain	Yes (Consumption of sashimi)	Nil	Enterorrhaphy of jejunum, piperacillin and amikacin for 1 week	Survived	
Mitra et al. [45]	F/3	Nil	Gastroenteritis	Blood	Fever, anorexia, vomiting, diarrhoea	Yes (Consumption of fish and unpasteurised milk)	Nil	Amoxicillin and metronidazole	Survived	
Chao et al. [46]	M/38	IgA nephropathy on peritoneal dialysis	Peritoneal dialysis-associated peritonitis	Peritoneal dialysis effluent	Abdominal pain, diarrhoea, turbid peritoneal dialysis effluent	No	Nil	Intraperitoneal cefazolin for 2 weeks	Survived	
Westberg et al. [47]	M/80	Chronic obstructive pulmonary disease, hypertension, hypercholesterolaemia, history of prostate cancer, total hip arthroplasty of the right hip, gastric and duodenal ulcers	Late onset periprosthetic infection of the right hip	Tissue biopsy of the right hip	Right hip and groin pain	No	Nil	Aminopenicillin for 8 weeks	Survived	
Choksi et al. [48]	M/78	Hypertension, diabetes mellitus, gastroesophageal reflux disease, morbid obesity	Urinary tract infection	Urine	Fever, haematuria, suprapubic tenderness	No	Nil	Broad spectrum antibiotics for 3 days, ceftriaxone for 4 days, cefpodoxime for 7 days	Survived	
Neagoe et al. [49]	M/79	Diabetes mellitus, polyarthritis rheumatica, obstructive sleep apnea syndrome, atrial fibrillation with pacemaker implantation, ischaemic heart disease, degenerative disc disease, obesity, antral gastritis, history of endoscopic Zenker's diverticulum repair, history of diverticulitis, right knee replacement due to osteoarthritis	Late onset periprosthetic infection of the right knee	Synovial fluid	Pain, swelling, and motility disorder of the right knee	Yes (Consumption of Nile perch)	Nil	Cefazolin for 24 days, arthroscopic lavage and synovectomy	Survived	
Mofredj et al. [50]	F/68	Cholangiocarcinoma treated with biliary stenting and steroid	Liver abscess	Blood	Gastrointestinal bleeding	No	Haemobilia	Removal of biliary stents, amoxicillin, metronidazole and netilmicin	Died	
Aubin et al. [51]	F/71	Obesity, hypertension, diabetes mellitus, hemochromatosis, ischaemic cardiomyopathy, chronic alcoholism, osteonecrosis of the femoral head with total hip replacement	Late onset periprosthetic infection of the left hip	Joint fluid and biopsy specimen	Left hip pain	Yes (Working as a fishmonger, frequent consumption of fish and shellfish)	Nil	Two stage exchange arthroplasty, ceftriaxone and levofloxacin for 3 months	Survived	
Kim et al. [52]	M/69	Fatty liver, chronic alcoholism with tobacco use, history of gastric ulcer with perforation treated with laparotomy	Acute acalculous cholecystitis	Bile and gallbladder tissue	Upper abdominal pain and postprandial abdominal pain	Yes (Consumption of raw freshwater fish and shellfish)	Nil	Laparoscopic cholecystectomy, cefminox for 3 days and cefaclor for 5 days	Survived	
Nakamura et al. [4]	M/81	Myelodysplastic syndrome	Bacteraemia from contaminated platelet transfusion	Blood	Fever, hypotension and faecal incontinence after platelet transfusion	No	Nil	Ceftriaxone and meropenem for 1 week	Survived	
Nadrah et al. [53]	M/81	Congestive heart failure, hypertension, chronic kidney disease, anaemia, pyrophosphate arthritis, diverticulosis of the colon, reflux oesophagitis, hypothyroidism, pacemaker insertion, mitral and aortic valve replacement	Bacteraemia	Blood	Fever, chills, myalgia, headache and malaise	No	Nil	Ampicillin for 6 weeks and gentamicin for 15 days	Survived	
Dylewski et al. [54]	M/90	Benign prostatic hypertrophy with transurethral prostate resection done	Urinary tract infection	Urine and blood	Chills and cloudy urine	No	Nil	Amoxicillin-clavulanate for 10 days	Survived	
Amarasinghe et al. [55]	M/52	Hypertension, schizophrenia, hepatitis C, chronic obstructive pulmonary disease/ asthma, alcohol abuse	Lumbar epidural abscess	Epidural abscess and blood	Low back pain	No	Nil	Ceftriaxone and Azithromycin for 6 weeks.	Died (due to unrelated causes)	
Colagrossi et al. [5]	M/9	Acute lymphoblastic leukaemia	Bacteraemia from contaminated platelet transfusion	Blood	Fever, raised serum inflammatory markers	No	Nil	Tigecycline, Amikacin, Ceftazidime/ avibactam	Survived	
Colagrossi et al. [5]	M/4	Acute lymphoblastic leukaemia	Bacteraemia from contaminated platelet transfusion	Blood	Fever, raised serum inflammatory markers	No	Nil	Tigecycline, Amikacin, β-lactams, Quinolones, Metronidazole	Survived	
Colagrossi et al. [5]	M/9	Acute lymphoblastic leukaemia	Bacteraemia from contaminated platelet transfusion	Blood	Fever, raised serum inflammatory markers	No	Nil	Tigecycline, Gentamicin, Quinolones	Survived	
Tessier et al. [56]	F/87	Heart failure, end-stage renal failure	Empyema thoracis	Blood, pleural fluid	Coffee-ground emesis, altered mental status, respiratory failure	Yes (Consumption of cooked fish)	Nil	Ceftriaxone, cefepime, metronidazole	Died	
Masudi et al. [57]	M/6	Nil	Wound infection	Wound	Bilateral leg abrasions with discharge	No	Nil	Cephalexin and topical gentamicin	Survived	
McPherson et al. [58]	M/65	Atrial fibrillation, gastrooesophageal reflux disease, history of renal cell carcinoma	Prosthetic knee joint infection	Joint fluid	Pain, warmth and swelling of left knee (6 months after total knee replacement)	No	Nil	Two-stage revision surgery. Ceftriaxone.	Survived	

The risk factors associated with L. garvieae infection include raw fish contact or consumption and underlying gastrointestinal diseases [6]. Exposure to raw fish was confirmed in one-third of patients with L. garvieae infection, among whom, 63.2% (12/19) developed IE. Gastrointestinal disorders were noted in 54.8% (17/31) and 42.3% (11/26) of IE and non-IE patients, respectively. Upper gastrointestinal disorders such as gastroesophageal reflux disease, gastritis or peptic ulcers were the most common, followed by lower gastrointestinal disorders including diverticulosis and colonic polyps. The use of gastric acid suppressants may facilitate the survival of the pathogen. Intestinal mucosal breaches due to polyps, diverticulosis or malignancies predisposes individuals to infection by providing a portal of entry [[6], [7], [8]]. Our patient consumed an assorted platter containing salmon, tuna and yellowtail from a sushi chain prior to the onset of his neurological symptoms. It is possible the patient acquired the infection from the sushi and sashimi in view of the temporal relationship between their consumption and his symptoms. However, a definitive relationship cannot be made as sampling of the food was not possible. Colonoscopy revealed two tubular adenomas which may have predisposed the patient to the infection.

Infectious intracranial aneurysms (IIAs) are most frequently caused by Staphylococcus aureus and viridans group streptococci, other bacteria such as coagulase-negative staphylococci, β-haemolytic streptococci, enterococci and Gram-negative bacteria such as the HACEK organisms (Haemophilus spp., Aggregatibacter spp., Cardiobacterium hominis, Eikenella corrodens and Kingella kingae) are sometimes implicated, while fungi may also cause IIAs especially in immunocompromised hosts [[9], [10], [11]]. There have been two reported cases of IIA due to L. garvieae, but both could be attributed to underlying IE. Watanabe et al. described a patient with L. garvieae native mitral valve endocarditis causing two IIAs, as well as cerebral and renal infarction [12]. Makhoul et al. reported a patient suffering from L. garvieae prosthetic aortic valve IE complicated by mycotic aneurysm in the inferior middle cerebral artery and left frontal haematoma [13]. To our knowledge, this is the first case of an IIA secondary to L. garvieae bacteraemia without concomitant IE. The distal PCA location, fusiform nature and histopathology of the aneurysm were highly suggestive of an infected aneurysm, as opposed to the more frequently encountered aneurysms that are generally saccular and located proximally at the circle of Willis.

β-lactam antibiotics such as penicillin and ceftriaxone are the drug of choice for L. garvieae infections [7,8,14]. Combination with aminoglycosides can be considered in severe infections to achieve a rapid bactericidal effect [1]. Clindamycin should be avoided as the organism is intrinsically resistant [14]. Neurosurgical or endovascular intervention should be considered in the case of IIAs, in addition to antibiotics.

In conclusion, we report a case of ruptured IIA associated with L. garvieae bacteraemia without concomitant IE. In managing invasive infections due to this organism, clinicians should seek history of raw fish exposure and underlying gastrointestinal pathologies. At-risk patients such as those with prosthetic heart valves should be educated to avoid consuming or handling raw fish to reduce the risk of L. garvieae infection and its potentially catastrophic complications.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Author contributions

C.H.L. and P.Y.M.W. contributed to the conception and design of the study. C.H.L. performed the literature search. C.H.L. and P.Y.M.W. analysed the data. C.H.L. and P.Y.M.W. and C.K.L.L. wrote the manuscript. K.S.N. provided the histopathological images. All authors were involved in critical revision of the manuscript and final approval of the manuscript.

Acknowledgments

We thank the staff at the clinical microbiology laboratory of Kwong Wah Hospital for technical support.

Declaration of competing interest

The authors declare that they have no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Data available statement

Data sharing is not applicable to this article as no data sets were generated or analyzed during the current study.

Ethics statement

Not applicable.

Informed consent

Informed consent was obtained from the patient for this study.
==== Refs
References

1 Gibello A Galán-Sánchez F Blanco MM The zoonotic potential of Lactococcus garvieae: an overview on microbiology, epidemiology, virulence factors and relationship with its presence in foods Res. Vet. Sci. 109 2016 59 70 10.1016/j.rvsc.2016.09.010 27892875
2 Vendrell D Balcázar JL Ruiz-Zarzuela I Lactococcus garvieae in fish: a review Comp. Immunol. Microbiol. Infect. Dis. 29 4 2006 177 198 10.1016/j.cimid.2006.06.003 16935332
3 Kozakai M Matsumoto M Matsumoto C First report of the isolation of Lactococcus garvieae from a platelet concentrate in Japan Transfusion (Paris) 56 10 2016 2602 2606 10.1111/trf.13752
4 Nakamura S Nakai K Sakata M Recipient sepsis caused by Lactococcus garvieae contamination of platelets from a donor with colon cancer Vox Sang. 114 2 2019 182 184 10.1111/vox.12740 30548621
5 Colagrossi L Costabile V Scutari R Evidence of pediatric sepsis caused by a drug resistant Lactococcus garvieae contaminated platelet concentrate Emerg. Microbes Infect. 11 1 2022 1325 1334 10.1080/22221751.2022.2071174 35475418
6 Malek A De la Hoz A Gomez-Villegas SI Lactococcus garvieae, an unusual pathogen in infective endocarditis: case report and review of the literature BMC Infect. Dis. 19 1 2019 301 10.1186/s12879-019-3912-8 30943906
7 Rösch RM Buschmann K Brendel L Lactococcus garvieae endocarditis in a prosthetic aortic valve: a case report and literature review J. Investig. Med. High Impact Case Rep. 7 2019 2324709619832052 10.1177/2324709619832052
8 Chan JFW Woo PCY Teng JLL Primary infective spondylodiscitis caused by Lactococcus garvieae and a review of human L. garvieae infections Infection 39 3 2011 259 264 10.1007/s15010-011-0094-8 21424437
9 Zanaty M Chalouhi N Starke RM Endovascular treatment of cerebral mycotic aneurysm: a review of the literature and single center experience BioMed Res. Int. 2013 2013 151643 10.1155/2013/151643
10 Allen LM Fowler AM Walker C Retrospective review of cerebral mycotic aneurysms in 26 patients: focus on treatment in strongly immunocompromised patients with a brief literature review AJNR Am. J. Neuroradiol. 34 4 2013 823 827 10.3174/ajnr.A3302 23064596
11 Peters PJ Harrison T Lennox JL A dangerous dilemma: management of infectious intracranial aneurysms complicating endocarditis Lancet Infect. Dis. 6 11 2006 742 748 10.1016/S1473-3099(06)70631-4 17067923
12 Watanabe Y Naito T Kikuchi K Infective endocarditis with Lactococcus garvieae in Japan: a case report J. Med. Case Rep. 5 2011 356 10.1186/1752-1947-5-356 21827685
13 Wahbah Makhoul G Mustafa A Ling J Lactococcus endocarditis after Bentall procedure presenting with intracranial hemorrhage IDCases 31 2023 e01710 10.1016/j.idcr.2023.e01710 36845909
14 Elliott JA Facklam RR Antimicrobial susceptibilities of Lactococcus lactis and Lactococcus garvieae and a proposed method to discriminate between them J. Clin. Microbiol. 34 5 1996 1296 1298 10.1128/jcm.34.5.1296-1298.1996 8727924
15 Zuily S Mami Z Meune C Lactococcus garvieae endocarditis Arch. Cardiovasc. Dis. 104 2 2011 138 139 10.1016/j.acvd.2010.05.005 21402350
16 Ortiz C López J Del Amo E Lactococcus garvieae infective endocarditis: report of 2 cases and review of the literature Rev. Esp. Cardiol. (Engl. Ed.) 67 9 2014 776 778 10.1016/j.rec.2014.04.008 25172081
17 Russo G Iannetta M D'Abramo A Lactococcus garvieae endocarditis in a patient with colonic diverticulosis: first case report in Italy and review of the literature New Microbiol. 35 4 2012 495 501 23109019
https://pubmed.ncbi.nlm.nih.gov/23109019/.

18 Lim SM Wong B Cross GB Lactobacillus garvieae endocarditis presenting with leg cramps IDCases 13 2018 e00427 10.1016/j.idcr.2018.e00427 30101072
19 Heras Cañas V Pérez Ramirez MD Bermudez Jiménez F Lactococcus garvieae endocarditis in a native valve identified by MALDI-TOF MS and PCR-based 16s rRNA in Spain: a case report N. Microbes N. Infect. 5 2015 13 15 10.1016/j.nmni.2015.02.001
20 Hirakawa TF Costa FA Vilela MC Lactococcus garvieae endocarditis: first case report in Latin America Arquivos Brasil. De Cardiol. 97 5 2011 e108 e110 10.1590/s0066-782x2011001400016
21 Tsur A Slutzki T Flusser D Lactococcus garvieae endocarditis on a prosthetic biological aortic valve Zoonoses Public Health 62 6 2015 435 437 10.1111/zph.12162 25295408
22 González-Bravo DH Alegre-Boschetti S Silva-Cantillo R Lactococcus garvieae: an uncommon human pathogen causing infective endocarditis in a valve-in-valve transcatheter aortic valve replacement Case Rep. Cardiol. 2021 2021 5569533 10.1155/2021/5569533
23 Rasmussen M Björk Werner J Dolk M Lactococcus garvieae endocarditis presenting with subdural haematoma BMC Cardiovasc. Disord. 14 2014 13 10.1186/1471-2261-14-13 24483839
24 Wilbring M Alexiou K Reichenspurner H Lactococcus garvieae causing zoonotic prosthetic valve endocarditis Clin. Res. Cardiol. Off. J. Ger. Card. Soc. 100 (6 2011 545 546 10.1007/s00392-011-0286-3
25 Fleming H Fowler SV Nguyen L Lactococcus garvieae multi-valve infective endocarditis in a traveler returning from South Korea Travel Med. Infect. Dis. 10 2 2012 101 104 10.1016/j.tmaid.2012.02.004 22397769
26 Lim FH Jenkins DR Native valve endocarditis caused by Lactococcus garvieae: an emerging human pathogen BMJ Case Rep 2017 2017 bcr2017220116 10.1136/bcr-2017-220116
27 Li WK Chen YS Wann SR Lactococcus garvieae endocarditis with initial presentation of acute cerebral infarction in a healthy immunocompetent man Intern. Med. 47 12) 2008 1143 1146 10.2169/internalmedicine.47.0795 18552475
28 Fihman V Raskine L Barrou Z Lactococcus garvieae endocarditis: identification by 16S rRNA and sodA sequence analysis J. Infect. 52 1 2006 e3 e6 10.1016/j.jinf.2005.04.021 15936823
29 Navas ME Hall G El Bejjani D A case of endocarditis caused by Lactococcus garvieae and suggested methods for identification J. Clin. Microbiol. 51 6 2013 1990 1992 10.1128/JCM.03400-12 23554190
30 Fefer JJ Ratzan KR Sharp SE Lactococcus garvieae endocarditis: report of a case and review of the literature Diagn. Microbiol. Infect. Dis. 32 2 1998 127 130 10.1016/s0732-8893(98)00065-0 9823537
31 Suh Y Kim MJ Seung Jung J Afebrile multi-valve infective endocarditis caused by Lactococcus garvieae: a case report and literature review Intern. Med. 55 8 2016 1011 1015 10.2169/internalmedicine.55.5935 27086823
32 Vinh DC Nichol KA Rand F Native-valve bacterial endocarditis caused by Lactococcus garvieae Diagn. Microbiol. Infect. Dis. 56 1 2006 91 94 10.1016/j.diagmicrobio.2006.02.010 16650958
33 Yiu KH Siu CW To KK A rare cause of infective endocarditis; Lactococcus garvieae Int. J. Cardiol. 114 2 2007 286 287 10.1016/j.ijcard.2005.11.092 16618510
34 Bazemore TC Maskarinec SA Zietlow K Familial adenomatous polyposis manifesting as Lactococcus endocarditis: a case report and review of the association of Lactococcus with underlying gastrointestinal disease Case Rep. Infect. Dis. 2016 2016 5805326 10.1155/2016/5805326
35 James PR Hardman SM Patterson DL Osteomyelitis and possible endocarditis secondary to Lactococcus garvieae: a first case report Postgrad. Med. J. 76 895 2000 301 303 10.1136/pmj.76.895.301 10775286
36 Backes Y Gruteke P Branger J Lactococcus garvieae endocarditis Ned. Tijdschr. Geneeskd 159 2015 A8738 26058767
https://pubmed.ncbi.nlm.nih.gov/26058767/.

37 Clavero R Escobar J Ramos-Avasola S Lactococcus garvieae endocarditis in a patient undergoing chronic hemodialysis. First case report in Chile and review of the literature Rev. Chilena Infectol. 34 4 2017 397 403 10.4067/s0716-10182017000400397 29165522
38 Landeloos E Van Camp G De Beenhouwer H Lactococcus garviae prosthetic mitral valve endocarditis: a case report and literature review Clin. Microbiol. Newsl. 39 16 2017 130 131 10.1016/j.clinmicnews.2017.08.002
39 Wang CY C Shie HS Chen SC Lactococcus garvieae infections in humans: possible association with aquaculture outbreaks Int. J. Clin. Pract. 61 1 2007 68 73 10.1111/j.1742-1241.2006.00855.x 16704679
40 Rojas-Velasco G Méndez-Hernández DP Escobar-Sibaja LE Lactococcus garvieae, an unusual etiology of prosthetic valve endocarditis. First case reported in Mexico Arch. Cardiol. Mex. 93 3 2023 369 371 10.24875/ACM.22000106 37553106
41 Sahu KK Sherif AA Syed MP A rare cause of sepsis: Lactococcus garvieae QJM 112 6 2019 447 448 10.1093/qjmed/hcz078 30924867
42 Lee JY Hyun M Kim HA Infectious spondylitis and septicemia due to Lactococcus garvieae: a literature review of non-endocarditis cases Infect. Chemother. 55 2 2023 285 289 10.3947/ic.2019.0015 33124212
43 Tandel K Bhatt P Ranjan P Meningitis caused by Lactococcus garvieae Med. J. Armed Forces India 73 1 2017 94 96 10.1016/j.mjafi.2015.08.004 28123254
44 Tariq EF Irshad Y Khalil HB Urinary tract infection caused by the novel pathogen, Lactococcus garvieae: a case report Cureus 12 7 2020 e9462 10.7759/cureus.9462 32874793
45 Mitra N Kumar P Lactococcus garvieae: an emerging pathogen Indian Pediatr. 52 9 2015 814 26519728
46 Chao CT Lai CF Huang JW Lactococcus garvieae peritoneal dialysis peritonitis Perit. Dial. Int. 33 1 2013 100 101 10.3747/pdi.2012.00078 23349199
47 Westberg M Brekke H Hermansen NO Late onset periprosthetic infection of the hip caused by the fish pathogen Lactococcus garvieae in a patient not associated with fish exposure J. Bone Jt. Infect. 5 3 2020 106 109 10.7150/jbji.43655 32566447
48 Choksi TT Dadani F Reviewing the emergence of Lactococcus garvieae: a case of catheter associated urinary tract infection caused by Lactococcus garvieae and Escherichia coli coinfection Case Rep. Infect. Dis. 2017 2017 5921865 10.1155/2017/5921865
49 Neagoe VI Zytoun S Neuhaus HJ First case report of a late onset knee periprosthetic joint infection caused by Lactococcus garvieae Case Rep. Orthop. 2016 2016 5053640 10.1155/2016/5053640
50 Mofredj A Baraka D Kloeti G Lactococcus garvieae septicemia with liver abscess in an immunosuppressed patient Am. J. Med. 109 6 2000 513 514 10.1016/s0002-9343(00)00534-9 11184774
51 Aubin GG Bémer P Guillouzouic A First report of a hip prosthetic and joint infection caused by Lactococcus garvieae in a woman fishmonger J. Clin. Microbiol. 49 5 2011 2074 2076 10.1128/jcm.00065-11 21367987
52 Kim JH Go J Cho CR First report of human acute acalculous cholecystitis caused by the fish pathogen Lactococcus garvieae J. Clin. Microbiol. 51 2 2013 712 714 10.1128/JCM.02369-12 23241376
53 Nadrah K Cerar T Papst L Lactococcus garvieae septicaemia in a patient with artificial heart valves Wien. Klin. Wochenschr. 123 21–22 2011 677 679 10.1007/s00508-011-0059-z 21935642
54 Joe D Urinary tract sepsis caused by Lactococcus garvieae Clin. Microbiol. Newsl. 36 4 2014 30 31 10.1016/j.clinmicnews.2014.01.007
55 Amarasinghe SN AL Fontenot HA. A curious case of Lactococcus garvieae bacteremia associated with adenocarcinoma IDCases 29 2022 e01557 10.1016/j.idcr.2022.e01557 35818444
56 Tessier S Emengo I Yoder N Massive empyema due to Lactococcus garvieae Germs 12 3 2022 414 418 10.18683/germs.2022.1347 37680679
57 Masudi B Litvinchuk T Byrd J Lactococcus garvieae in rural Alabama: a case report Cureus 15 5 2023 e39560 10.7759/cureus.39560 37378249
58 McPherson EJ Ishmael CR Zukotynski B Lactococcus garvieae periprosthetic joint infection in a cattle rancher with a total knee arthroplasty: a novel reservoir transmission J. Orthop. Case Rep. 12 11 2022 76 82 10.13107/jocr.2022.v12.i11.3422
