Isolated Renal Mucormycosis in Immunocompetent Hosts: Clinical Spectrum and Management Approach

Abstract

Isolated renal mucormycosis in immunocompetent hosts is a rare entity. We present the largest case series of isolated renal mucormycosis in immunocompetent hosts. Retrospective data of isolated renal mucormycosis from March 2012 to June 2017 was reviewed. Fifteen patients of isolated renal mucormycosis were identified. Contrast-enhanced computed tomography scan showed enlarged globular kidneys with decreased or patchy enhancement, perinephric stranding and thickened Gerota's fascia in all patients. Ten patients with unilateral involvement underwent nephrectomy and two of four patients with bilateral renal mucormycosis underwent bilateral nephrectomy. Two patients were managed with intravenous antifungal therapy alone. Overall, the mortality rate in our series was 40% (6/15). Isolated renal mucormycosis in healthy immunocompetent hosts is an emerging new entity. Prompt diagnosis based on the characteristic clinical and radiological picture and starting high-dose antifungal therapy at least 24 hours before surgical debridement offer the best chance of survival in these patients.

Figure 1.

(A) Large areas of bland necrosis and area of inflammatory infiltrate composed of lymphocytes, eosinophils, and polymorphs (10×). (B) Scattered multinucleated giant cells in a background of fibrosis (20×). (C) Scattered fungal hyphae seen in the background of bland necrosis (20×). (D) Fungal hyphae are aseptate, show right-angled branching and have a thick cell wall in a background of bland necrosis. (E) PAS stain showing fungal hyphae with right-angled branching, devoid of septa, thick cell membrane and typical foldable appearance. Histomorphologically highly suggestive of mucormycosis. This figure appears in color at www.ajtmh.org.

Figure 2.

Characteristic contrast-enhanced computed tomography scan findings showing completely nonenhancing right kidney with perinephric fat stranding (arrow) in A, patchy area of decreased enhancement in the right kidney (arrow) in B, thickened Gerota’s fascia in C (arrow), and bulky psoas muscle in D (arrow). This figure appears in color at www.ajtmh.org.

Figure 3.

Algorithm for the management of suspected renal mucormycosis.