November 2022 Medical Image of the Month: COVID-19 Infection Presenting as Spontaneous Subcapsular Hematoma of the Kidney

Figure 1. Enhanced abdominal CT images in the axial (A) and coronal (B) reconstruction planes show uniform high attenuation material surrounding the right kidney but conforming to renal shape consistent with subcapsular hematoma (arrows).  Note the reactive perinephric stranding in the right retroperitoneal space.

A 57-year-old woman with pertinent medical history of hypertension presented to the emergency department with 3 days of right sided lower abdominal pain radiating to the flank, associated with nausea and nonbloody, nonbilious emesis. She reported recent travel to Florida where she visited amusement parks, but only rode small children’s rides with no experienced physical trauma. She experienced fatigue and chills 5 days prior to presentation and tested positive for SARS-CoV2 virus on admission. She had been vaccinated for COVID-19 x3 (Moderna). No other significant history nor medications were noted, and review of systems was otherwise unremarkable. 

Urinalysis demonstrated mild ketonuria (20), proteinuria (100) and moderate hematuria on urinalysis while BUN and creatinine remained stable at baseline throughout. Physical examination confirmed costovertebral angle tenderness to the right side. CT abdomen revealed an American Association for the Surgery of Trauma (AAST) grade 3 right renal subcapsular hematoma with 2.1 cm laceration and striations with a pre-existing right arterial aneurysm. Care was escalated to ICU for closer renal function monitoring; urology and nephrology were consulted for suspected ischemic nephropathy and renal compression with concern for Page (external compression) kidney . After exclusion of traumatic and known causes, interdisciplinary discussion came to the consensus of COVID-19 infection induced SRH.

Subcapsular renal hematoma (SRH) is a challenging medical condition in which hematoma formation may exert pressure on surrounding parenchyma resulting in hypoperfusion or ischemia, with overt concern for rupture with subsequent hemorrhage and hemodynamic instability. While this is a predominantly a medical condition precipitated by neoplasms, abdominal trauma or anticoagulant use, sporadic cases of SRH have been observed since the onset of the COVID-19 pandemic. Here, we present a rare case and imaging of COVID-19 infection induced SRH.

Even three years since the start of the COVID-19 pandemic, clinicians continue to unravel COVID-19’s impact on various body systems. While renal involvement is observed in the form of acute kidney injury in over 30% of hospitalized COVID-19 patients (1), SRH has rarely been documented. Retroperitoneal bleeding from various organs has occurred in COVID-19 patients, but this bleeding is often secondary to prophylactic anticoagulation to combat the suspected inflammation-induced hypercoagulable state (2-4). Seldom does retroperitoneal bleeding occur in the absence of anticoagulant use or other precipitating cause, as is seen in our patient with SRH. Tavoosian et al. (5) illustrate a similar case of an otherwise healthy, COVID-19 positive individual that developed spontaneous subcapsular renal hematoma without history of malignancy, trauma or anticoagulant use. The mechanism by which spontaneous SRH may occur in COVID-19 patients is still unclear. However, our case adds to literature another presentation of spontaneous SRH caused by COVID-19 infection with unique imaging findings and add to the growing differential for causes of SRH and the differential of abdominal pain. 

Kally Dey¹, Shil Punatar DO², Tauseef Sarguroh MD²

¹ Midwestern University Chicago College of Osteopathic Medicine, Downers Grove, IL USA

² Franciscan Health Olympia Fields, Olympia Fields, IL USA

References

1. Hirsch JS, Ng JH, Ross DW, et al. Acute kidney injury in patients hospitalized with COVID-19. Kidney Int. 2020;98(1):209-218. [CrossRef] [PubMed]
2. Patel I, Akoluk A, Douedi S, et al. Life-Threatening Psoas Hematoma due to Retroperitoneal Hemorrhage in a COVID-19 Patient on Enoxaparin Treated With Arterial Embolization: A Case Report. J Clin Med Res. 2020;12(7):458-461. [CrossRef] [PubMed]
3. ​​Cattaneo M, Bertinato EM, Birocchi S, et al. Pulmonary Embolism or Pulmonary Thrombosis in COVID-19? Is the Recommendation to Use High-Dose Heparin for Thromboprophylaxis Justified?Thromb Haemost. 2020;120(8):1230-1232. [CrossRef][PubMed]
4. Zhou F, Yu T, Du R, et al. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. Lancet. 2020 Mar 28;395(10229):1054-1062. Erratum in: Lancet. 2020 Mar 28;395(10229):1038.[CrossRef] [PubMed]
5. Tavoosian A, Ahmadi S, Aghamir SMK. Spontaneous perirenal haematoma (SPH) in a COVID-19 patient: A rare case report. Urol Case Rep. 2022 May;42:102006.[CrossRef] [PubMed]

Cite as: Dey K, Punatar S, Sarguroh T. November 2022 Medical Image of the Month: COVID-19 Infection Presenting as Spontaneous Subcapsular Hematoma of the Kidney. Southwest J Pulm Crit Care Sleep. 2022;25(4):67-68. doi: https://doi.org/10.13175/swjpccs041-22 PDF

Medical Image of the Week: Renal Cell Carcinoma Metastasis

Figure 1. Panel A: Axial CT image noncontrast showing small pulmonary nodules concerning for metastasis. Panel B: Axial CT image depicting 15 cm mass, originating from the right acetabulum and adjacent iliac bone. Panel C: Coronal CT image showing prominent left renal cyst measuring almost 40 mm. Panel D: Coronal CT image displaying femoral head intact but surrounded by abnormal soft tissue, concerning for neoplasm. There is bony destruction and lytic process in the anterior and posterior pillars of the right acetabulum.

A 65-year-old man was complaining of progressive weakness and right knee pain with limping since November 2014 was admitted recently to a local hospital and treated for chronic kidney disease related anemia, Klebsiella urinary tract infection and methicillin-sensitive Staphylococcus aureus wound infections. He was discharged to rehab, but continued to have progressive weakness, pain and limping. He was sent to our hospital for further evaluation and imaging.

CT of the abdomen and pelvis non contrast, due to decreased glomerular filtration rate, revealed a 15 cm mass originating from the right acetabulum and adjacent iliac bone with bony destruction and lytic processes (Figure 1). The femoral head is also surrounded by abnormal soft tissue (Figure 1D). There were also small pulmonary nodules (Figure 1A), small lymph nodes in the transverse mesocolon and retroperitoneum, and an enlarged left adrenal gland concerning for other metastasis.

CT guided biopsy of the lesion revealed a neoplastic process composed of atypical cells with centrally placed nuclei, abundant clear cytoplasm arranged in a vascular network. Immunohistochemical stains demonstrated positivity for the following: vimentin, low molecular weight keratin, CD10, RCCA, and PAX-8. These findings are consistent with metastatic renal cell carcinoma.

A total body bone scan with Tc-99m methylene diphosphonate, performed to locate other osseous metastasis, was negative for distant metastasis other than the large destructive lesion destroying the right ileum previously noted on CT.

Renal cell carcinoma (RCC) is a cortical tumor with malignant cells originating from the epithelial lining of the proximal tubules. Renal cancer is amongst the 10 most common cancers in both men and women, with RCC accounting for about 80% of the total incidence and mortality (1). RCC has been referred to as “the internist’s tumor” as it can cause systemic symptoms unrelated to the renal cancer. The classic triad of RCC (flank pain, hematuria, and a palpable abdominal renal mass) occurs in at most 9 percent of patients (1). Most cases of RCC are diagnosed incidentally on radiographic investigation done for other reasons. Unfortunately, many patients are asymptomatic until the disease is advanced. At presentation, approximately 25% of individuals either have distant metastases or advanced local disease (2). Biopsy is not usually required to diagnose RCC. Contrast-enhanced CT can be used to diagnosis and stage RCC. 

Stage IV disease has a median survival of about 12 months with systemic cytokine therapy and 28 months with targeted therapies, based on analyses from the International Metastatic RCC Database Consortium (IMDC) (1,3).

Erin Yen MS¹, Benjamin Rayikanti MD², Yunuen Valenzuela MD³, Jennifer Segar MD³

¹ Midwestern University Arizona College of Osteopathic Medicine, Phoenix

² Tucson Hospitals Medical Education Program

³ Department of Internal Medicine, Banner University Medical Center Tucson

Tucson AZ USA

References

1. American Cancer Society. Cancer Facts & Figures 2016. Atlanta, GA: American Cancer Society; 2016. Available at: http://www.cancer.org/research/cancerfactsstatistics/cancerfactsfigures2016/ (accessed 9/14/16).
2. DeKernion JB. Real numbers. In: Campbell's Urology, Walsh PC, Gittes RF, Perlmutter AD (Eds), WB Saunders, Philadelphia 1986. p.1294.
3. Heng DY, Choueiri TK, Rini BI, et al. Outcomes of patients with metastatic renal cell carcinoma that do not meet eligibility criteria for clinical trials. Ann Oncol. 2014 Jan;25(1):149-54. [CrossRef] [PubMed]

Cite as: Yen E, Rayikanti B, Valenzuela Y, Segar J. Medical image of the week: renal cell carcinoma metastasis. Southwest J Pulm Crit Care. 2016;13(3):135-6. doi: http://dx.doi.org/10.13175/swjpcc068-16 PDF