==== Front Cureus Cureus 2168-8184 Cureus 2168-8184 Cureus Palo Alto (CA) 10.7759/cureus.11242 Internal Medicine Radiology A Renal Colic Mimic - Wunderlich Syndrome: A Case Report Muacevic Alexander Adler John R Sirajudeen Jaseem 1 Purayil Nishan K 1 Parambath Arif 2 Kayakkool Muhammed 1 1 Internal Medicine, Hamad Medical Corporation, Doha, QAT 2 Radiology, Hamad Medical Corporation, Doha, QAT Jaseem Sirajudeen jsirajudeen@hamad.qa 29 10 2020 10 2020 12 10 e1124229 10 2020 Copyright © 2020, Sirajudeen et al.2020Sirajudeen et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This article is available from https://www.cureus.com/articles/42297-a-renal-colic-mimic---wunderlich-syndrome-a-case-reportWunderlich syndrome is a rare clinical syndrome characterized by the sudden onset of spontaneous, nontraumatic hemorrhage into renal subcapsular and retroperitoneal region. We present the case of a 24-year-old hypertensive who presented with acute flank pain and was found to have perinephric hematoma. He was managed conservatively and the follow-up revealed complete resolution of the hematoma with no structural abnormality of kidney. His connective tissue disorder/vasculitis work up was also normal. wunderlich syndromeperinephric hematomaThe content published in Cureus is the result of clinical experience and/or research by independent individuals or organizations. Cureus is not responsible for the scientific accuracy or reliability of data or conclusions published herein. All content published within Cureus is intended only for educational, research and reference purposes. Additionally, articles published within Cureus should not be deemed a suitable substitute for the advice of a qualified health care professional. Do not disregard or avoid professional medical advice due to content published within Cureus. ==== Body Introduction Acute abdominal pain is a common presenting complaint in patients visiting the ED. Such cases often prove a diagnostic challenge to emergency physicians, especially if the patients are hemodynamically unstable, elderly, and women of childbearing age group [1]. Spontaneous renal hemorrhage (Wunderlich syndrome) can mimic such a presentation. Neoplasm is the most common cause; however, various other etiologies have been identified [2]. Patients might even require surgical intervention for control of bleeding. Case presentation A 24-year-old male presented to our ED with complaints of right flank pain, with sudden onset, and rapid progression. The pain was localized to the right flank. There was no associated radiation of pain, fever, hematuria, or history of trauma. He also complained of two episodes of vomiting. He had been on regular medication for hypertension and chronic renal failure. Upon arrival, the patient was afebrile, blood pressure (BP) was 114/70, pulse rate was 88 beats/min, room air saturation 100%, and respiratory rate was 22 breaths/min. Systemic examination of the abdomen was soft with tenderness over the right lower quadrant, with a palpable mass over the renal angle. Another systemic examination was unremarkable. Blood investigations revealed hemoglobin (Hgb) 10.7 g/dL (baseline Hgb 13.7 g dL), creatinine 222 umol/L, urine microscopy blood 3+, and protein 3+ (Table 1). Table 1 Laboratory values. WBC, white blood cells; Hgb, hemoglobin; eGFR, estimated glomerular filtration rate; bilirubin T, bilirubin total; ALT, alanine transaminase; AST, aspartate amino transferase; TIBC, total iron binding capacity; PTH, parathyroid hormone; POC Urine, point of care urine analysis; LEUKO, leukocytes; NIT, nitrites; PRO, protein; GLU, glucose; KET, ketones; URO, urobilinogen; BIL, bilirubin; SG, specific gravity; BLD, blood Group Test Result Normal range General hematology WBC 6.90 x 10^3/uL 4.00-10.00   Hgb 13.1 g/dL 13.0-17.0   Platelet 287 x 10^3/uL 150-400 Blood chemistry Urea 7.00 mmol/L 2.76-8.07   Creatinine 242 umol/L 62-106   eGFR 27 mL/min     Sodium 139 mmol/L 136-145   Potassium 3.4 mmol/L 3.5-5.1   Chloride 99 mmol/L 98-107   Bicarbonate 26 mmol/L 22-29   Calcium 2.26 mmol/L 2.15-2.50   Calcium Corr 2.34 mmol/L 2.20-2.55   Phosphorus 1.13 mmol/L 0.81-1.45   Magnesium 0.82 mmol/L 0.66-1.07   Bilirubin T 5 umol/L 0-21   Total protein 69 g/L 66-87   Albumin Lvl 36.0 g/L 35.0-52.0   Uric acid 373 umol/L 202-416   Alk phos 76 U/L 40-129   ALT 16 U/L 0-41   AST 17 U/L 0-40   Cholesterol 4.0 mmol/L <5.2   Triglyceride 1.1 mmol/L <1.7   Iron 5 umol/L 6-35   TIBC 53 umol/L 45-80   Transferrin 2.1 g/L 2.0-3.6   Fe% saturation 9% 15-45   Glucose 4.6 mmol/L 3.3-5.5 Endocrinology Vit D 13 ng/mL     PTH 75.6 pg/mL 15.0-65.0   Vit B12 252.0 pmol/L 145.0-596.0 Autoimmune diseases Anti cardiolipin Ab IgG 1.00 GPL     Anti cardiolipin Ab IgM <0.80 MPL     Anti GBM Ab <1.9 U/mL     Anti ds DNA 0.0.5 IU/L     ANCA Negative     C3 137 mg/dL 90-180   C4 27 mg/dL 10-40 Bacteriology Blood culture No growth   POC urine Ur pH  - POC 6.0     Ur LEUKO - POC Negative     Ur NIT - POC Negative     Ur PRO - POC 3+     Ur GLU - POC Negative     Ur KET -POC Negative     Ur URO - POC 3.2 umol/L     Ur BIL - POC Negative     Ur SG - POC 1.020     Ur BLD - POC 3+   Urine culture No growth     Given his persistent pain over the flank region, with renal dysfunction, a noncontrast computed tomography-kidney ureter bladder (CT-KUB) was performed, showing enlarged right kidney with perinephric fat stranding and isodense lesion in the perinephric space, showing a CT density of recent bleed [(45-50 Hounsfield unit (HU)] (Figure 1). Figure 1 Noncontrast CT-KUB showing enlarged right kidney with perinephric fat stranding and isodense lesion in the perinephric space (arrow), showing a CT density of recent bleed (45-50 HU). CT-KUB, computed tomography-kidney ureter bladder; HU, Hounsfield unit The patient was hospitalized for further workup and management and was started on analgesics and antibiotics. After two days of hospitalization, the patient underwent an MRI abdomen with contrast, showing a large perinephric hematoma (arrowhead) and a small hemorrhagic cyst (arrow) in the anterior renal cortex communicating with perinephric hematoma (Figure 2). Figure 2 MRI showing large perinephric hematoma (arrow head) and a small hemorrhagic cyst ( arrow) in anterior renal cortex communicating with perinephric hematoma. He was treated symptomatically. The patient was pain-free and hemodynamically stable. The urology team was consulted, who advised for conservative management and close observation. He did not have a further fall in Hgb or worsening of renal function. Further workup for other causes, like vasculitis, were negative. On the eighth day of admission, ultrasound imaging of the kidney revealed an estimate of 208 cc of perinephric fluid collection (Figure 3).  Figure 3 Ultrasound: showing perinephric hematoma (arrowhead) communicating with hemorrhagic cyst (arrow). As the patient improved symptomatically, he was discharged with outpatient follow-up. Follow-up ultrasounds done in the first and third weeks after discharge demonstrated regression of hematoma. Follow-up ultrasound done after three months postdischarge demonstrated complete resolution of hematoma, and no evidence of malignancies was detected (Figure 4). Figure 4 Follow-up ultrasound after three months showing total resolution of perinephric hematoma. Discussion Wunderlich syndrome is a rare clinical syndrome characterized by a sudden onset of spontaneous, nontraumatic hemorrhage into the renal subcapsular and retroperitoneal region [3]. This syndrome was first described by Wunderlich in 1856 [4]. A meta-analysis in 2002 by Zhang et al. described 165 patients of spontaneous nontraumatic hemorrhage over 15 years between 1985 and 1999 [2]. Clinical presentation is often characterized by a constellation of symptoms known as the Lenk’s triad -- acute onset flank pain, palpable flank mass, and hypovolemic shock [4]. However, a study observed that the typical presentation was seen in only 20%-30% of the cases [5].  Other presentations include fever, nausea, vomiting, and hematuria. The most common underlying pathology in up to 60% of cases are neoplasms which mostly include renal angiomyolipoma and renal cell carcinoma [3]. These neoplasms arise from the proliferation of epithelioid cells present around the blood vessels. Renal cell carcinoma is the most common malignant neoplasm. Rupture of the renal artery, arteriovenous malformation, nephritis, renal calculi, cystic medial necrosis, segmental arterial mediolysis, polyarteritis nodosa, and cystic rupture are the other common etiologies [2, 4].  No underlying etiology could be found in our patient, as seen in a few other reported Wunderlich syndrome cases. In our case, the initial presentation mimicked renal colic. Early diagnosis can be aided by accurate clinical assessment and appropriate imaging. The initial imaging of choice is an ultrasound abdomen, although abdominal CT has a 100% sensitivity [6-8]. The MRI of the abdomen further confirmed our diagnosis. Exploratory laparotomy or nephrectomy is done for most patients. However, in our case, as no underlying malignancy was detected on initial CT, we chose to opt for conservative management with close clinical monitoring and follow-up imaging. This option can also be considered in stable patients with no evidence of malignancy on CT/MRI. This conservative approach can avoid the need for surgery. Conclusions It would be prudent to remember Wunderlich syndrome as a differential diagnosis in patients presenting with unexplained abdominal pain to ED. The authors have declared that no competing interests exist. Human Ethics Consent was obtained by all participants in this study ==== Refs References 1 The use of abdominal computed tomography in older ED patients with acute abdominal pain Am J Emerg Med Hustey FM Meldon SW Banet GA Gerson LW Blanda M Lewis LM 259 265 23 2005 15915395 2 Etiology of spontaneous perirenal haemorrhage: a meta-analysis Rev Urol Zhang JQ Fielding JR Zou KH 36 40 8 2006 https://pubmed.ncbi.nlm.nih.gov/11912370/ 16985559 3 Wunderlich syndrome: cross-sectional imaging review J Comput Assist Tomogr Katabathina VS Katre R Prasad SR Surabhi VR Shanbhogue AK Sunnapwar A 425 433 35 2011 21765296 4 Spontaneous retroperitoneal hemorrhage caused by segmental arterial mediolysis J Urol Phillips CK Lepor H 1593 1596 167 2002 https://pubmed.ncbi.nlm.nih.gov/16985559/ 11912370 5 Wünderlich syndrome: an unusual cause of flank pain Am J Emerg Med Beaumont-Caminos C Jean-Louis C Belzunegui-Otano T Fenández-Esain B Martínez-Jarauta J GarcíaSanchotena JL 474 29 2011 https://doi.org/10.1016/j.ajem.2010.04.019 6 Wünderlich's syndrome: causes, diagnosis and radiological management Clin Radiol Albi G del Campo L Tagarro D 840 845 57 2002 https://doi.org/10.1053/crad.2002.0981 12384111 7 Aetiology, diagnosis and management of spontaneous perirenal haematomas Eur Urol Brkovic D Moehring K Doersam L 302 307 29 1996 https://doi.org/10.1159/000473765 8740036 8 Spontaneous subcapsular renal hematoma: a case report and review of literature Urol Ann Baishya RK Dhawan DR Sabnis R 44 46 3 2011 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3037002/ 21346835