Disseminated Mucormycosis in a Patient with Recent Kidney Transplantation: A Case Report and Review of the Literature
A 47-year-old Hispanic man with a history of end-stage kidney disease secondary to diabetic nephropathy underwent deceased donor renal allograft transplantation. His immediate posttransplant course was unremarkable, with prompt functioning of his allograft and decreasing creatinine levels. His immunosuppressant regimen included tacrolimus, mycophenolate sodium and corticosteroids. Ten days after the transplant, he developed suprapubic abdominal pain that was thought to be due to the indwelling ureteral stent, necessitating its removal with complete resolution of his discomfort.\nApproximately 5 weeks following his transplant, the patient presented with fatigue, diarrhea and oligoanuria, without any associated fever or respiratory symptoms. He had significant allograft dysfunction with a creatinine level of 8.1 mg/dl up from a nadir of 2.7 mg/dl. Doppler ultrasound of the renal allograft showed an area of hypoperfusion affecting the upper pole of the renal allograft, with a moderate degree of hydronephrosis. A percutaneous nephrostomy tube was placed without any improvement in urine output or renal function. A renal allograft biopsy was then done to further elucidate the etiology of his graft dysfunction. This revealed diffuse C4d-positive staining in the peritubular capillaries suggestive of acute humoral rejection; however, the biopsy was also remarkable for numerous, broad, ribbon-like, nonseptate, fungal hyphae with wide-angle branching suggestive of Mucor infection. There was a focal cortical infarct accounting for approximately 10% of the overall biopsy, with focal small vessels containing fungal hyphae (fig. ). The patient was prepared for transplant nephrectomy and arteriovenous fistula thrombectomy. Postoperatively, his anti-rejection medications were discontinued, amphotericin B and micafungin were started and hemodialysis was initiated.\nA pathology exam performed after the nephrectomy (fig. ) showed significant cortical infarction involving more than half of the cortex, with patchy, widespread involvement of fungal hyphae that involved the ureteral lumen, ureteral wall, renal parenchyma and numerous large and small vessels. Chest CT showed a large right upper lobe cavitating mass measuring 4.9 × 2.8 cm, with scattered areas of smaller nodules present throughout both lungs (fig. ). Abdominal CT revealed a wedge-shaped area of hypodensity within the anterior spleen compatible with infarction, along with additional areas of hypodensity within the spleen. There was also a nonspecific hypodensity in the right hepatic lobe. Head and maxillofacial CT were normal. The patient underwent a CT-guided biopsy of the right upper lobe of the lung, and pathology confirmed the clinical suspicion of disseminated mucormycosis. Within 1 week of presentation, the patient became hemodynamically unstable, requiring a transfer to the intensive care unit for mechanical ventilation and vasopressor support. As his mental status showed significant decline, a repeat head CT was done. This revealed interval development of areas of subcortical hypoattenuation involving the bilateral frontal lobes, bilateral occipital lobes and bilateral cerebral hemispheres, suggesting multifocal cerebritis with no abscesses (fig. ). The patient's condition continued to deteriorate, and he developed supraventricular tachycardia and the inability to tolerate hemodialysis. His family elected for comfort care and the patient subsequently died.\nThe patient's records did not reveal any previous history of significant upper or lower respiratory symptoms, and his previous chest X-rays, including the one that was done just before his transplant surgery, were unremarkable. A renal allograft biopsy was done on the recipient of the donor-matched organ (the second donor kidney) and showed no evidence of fungal infection, which made it unlikely to be a donor-transmitted infection.