Discussion
Mucormycosis is an infection due to fungi (order Mucorales) of species
Rhizopus, Mucor, Cunninghamella, Apophysomyces, Lichtheimia,
Rhizomucor.[4]
These are angioinvasive fungi, which invades kidneys hematogenously as
part of multi -organ disease, although isolated renal involvement is
also reported. [1, 3]
Mucor is an ubiquitous fungi which reaches the human body through spores
entrapped in nasal turbinates or through ingestion , inhalation or
interrupted skin. This infection is seen commonly in diabetics,
immunocompromised patients such as allograft recipients, HIV patients,
patients with malignancy and intravenous (IV) drug abusers. [1,5]
The virulence factor involved in the pathogenesis of Mucorales are
high-affinity iron permease (FTR1), Spore coat protein (Cot H) and
ADP-ribosylation factor which allows fungi to tolerate a low iron
environment, impairing host defences and growth of Mucorales. [6]
Neutrophils are the mainstay to mount a response against mucor, hence
patients with neutropenia or dysfunction in neutrophils (steroid use,
diabetes Mellitus) results in fulminant fungal infection. [7]
On basis of location, mucormycosis can be divided into rhinocerebral,
pulmonary, cutaneous, gastrointestinal, disseminated, and uncommon
presentations. [8]
Suspecting and timely diagnosis is required for successful treatment of
mucormycosis.
In genitourinary organs, mucormycosis is reported in kidneys, although
involvement of other organs reported occasionaly. It can present with
flank pain, fever, acute kidney injury, lump. Diagnosis is by clinical
suspicion, radiology, smear examination, culture, and histopathological
examination. When culture is not available or could not be done,
histopathology is the mainstay of diagnosis. [9]
Examination with stains hematoxylin and eosin (H&E) or Grocott
methenamine-silver (GMS) or periodic acid-Schiff (PAS) stains show
typical broad, nonseptate, irregular, ribbon-shaped (typically 6- to
25-µm diameter), irregular branching at 45-90º. Histopathology from
tissue shows necrosis and angioinvasion with neutrophils as predominant
inflammatory response. A granulomatous response may be seen in delayed
stages. [10]
Treatment can be medical as well as surgical as per the condition of the
patient. Amphotericin B (liposomal) is first-line treatment with
Posaconazole, isavuconazole as alternatives.
Espejo et al reported a case of bladder mass detected and managed
medically. They described the presence of fungal mass in a patient with
DM and CKD (chronic kidney disease). [1]
In a case series by Devana et al ,15 patients of isolated renal
mucormycosis were described. Ten underwent unilaterally nephrectomy and
2 underwent bilateral nephrectomy whereas 2 were managed medically for
mucormycosis. [2]
In our patient patient complained of low-grade fever. Investigations
suggested right mild hydronephrosis with no renal changes of
mucormycosis with echogenic contents in urinary bladder. Patient was
taken up for cystoscopy and stenting. On cystoscopy elongated creamy
yellow material wwas seen in urinary bladder. Histopathology suggested
mucormycosis in urinary bladder. He was started on oral Posaconazole and
improved considerably. Follow up investigation revealed normal kidneys
and normal creatinine (1.1mg/dl).