Perforation Peritonitis Secondary to Intestinal Mucormycosis in a Boy with Type I Diabetes Mellitus.

Intestinal mucormycosis is a rare fungal infection reported more commonly in immunocompromised patients, premature infants, diabetics, transplant recipients, prolonged use of corticosteroids, or in conditions associated with an increased availability of serum iron such as acidosis or deferoxamine administration and carries a high mortality rate. We report the case of a 14-year-old boy with diabetes mellitus, who presented with atypical clinical features. He was diagnosed as intestinal mucormycosis and was treated successfully with surgical and antifungal management. Copyright:

INTRODUCTION

Mucormycosis is a life-threatening infection caused by fungi of the subphylum Mucoromycotina, order Mucorales.[1] Traditional risk factors for the development of invasive mucormycosis include diabetes, defects in host phagocytes, corticosteroid use, organ or stem cell transplantation, and increased levels of available serum iron as a result of acidosis or administration of deferoxamine.[23] In recent years, the disease has also increasingly been described in patients without traditional risk factors.

Gastrointestinal mucormycosis is an uncommon opportunistic fungal infection, often seen in immunocompromised patients. We present a rare case of invasive intestinal mucormycosis presenting as perforation peritonitis, in a schoolboy who was recently diagnosed with type 1 diabetes mellitus.

CASE REPORT

A 14-year-old schoolboy presented to the emergency department with acute abdominal pain of 3 days' duration. He was admitted to a rural hospital, where he was diagnosed as having diabetes mellitus and was treated for the same. His symptoms did not improve, so he was sent to our institute.

The patient was examined in the emergency department and was diagnosed to have diabetic ketoacidosis with acute pain in the abdomen. Clinical examination demonstrated that the patient was vitally stable, and abdominal distension was present with tenderness all over, but abdominal muscle guarding was absent. Inflammatory markers were within normal limits, C-reactive protein was positive, his renal parameters were raised with blood urea being 113.6 mg/dL, and serum creatinine was 2.0 mg/dL. His blood glucose level was 464 mg% and urine was positive for ketones. The patient was admitted to the intensive care unit for the management of ketoacidosis, where he received insulin therapy. After the patient was stabilized, an X-ray of the abdomen was done which showed few gas-filled loops, but no free intraperitoneal gas. An ultrasonography of the abdomen was done, which was reported as gross ascites. After this, contrast-enhanced computed tomography scan of the abdomen and pelvis was done [Figure 1]. It showed dilated jejunal and ileal loops with multiple air-fluid levels with the largest diameter of 3.7 cm. There was suboptimal bowel wall enhancement with focal discontinuation of its wall with few extraluminal air foci in mid-ileal loops and cecum suggestive of ischemic necrosis. The patient was transferred to the surgical ward, where he was resuscitated and antibiotics were started and he was posted for exploratory laparotomy. Intraoperatively, he was found to have around 1 litre of bilious collection and multiple ulcers involving ileum and cecum with multiple perforations [Figure 2a]. A resection of the ileum and cecum was done, and a double-barrel stoma was fashioned with the exteriorized colon and jejunum.

Figure 1

Focal discontinuity in the wall of distal ileum with extraluminal air foci and suboptimal enhancement suggestive of necrosis

Figure 2

(a) Resected specimen showing edematous and inflamed bowel with areas having slough, multiple ulcers and perforations. (b) Photomicrograph showing mucor fungal hyphae (periodic acid–Schiff stain, ×40)

Histopathological examination of the small intestinal specimen showed ulceration and necrosis of mucosa, congestion, and minimal inflammatory infiltrate comprising eosinophils and polymorphs in the whole intestinal wall. Granulomas were seen in subserosal layer. Serosal surfaces showed areas of necrosis and serositis and fungal hyphae. Fungal hyphae were broad and aseptate and were periodic acid–Schiff stain positive suggestive of intestinal mucormycosis [Figure 2b].

Postoperatively, antibiotics were continued and the patient was put on total parenteral nutrition. After histopathological confirmation, the patient was put on injectable amphotericin B for 21 days. His renal function tests were monitored. His abdominal wound healed well.

The patient was discharged after 3 weeks. There was no evidence of abdominal symptoms, his stoma was functioning well, and he had normal inflammatory markers. The patient was put on oral posaconazole. At the monthly follow-up visits, the patient was found to be doing well, baring his diabetic control. The stoma closure could only be done after 1 year due to his uncontrolled diabetes. After the closure of stoma, a biopsy from the proximal and distal loop and the peritoneum was obtained during stoma closure and sent for histopathology. The report did not show any evidence of fungal infection. The patient continues to be on oral posaconazole and is doing well. A decision to continue with posaconazole or not will be made by clinical examination of the patient on subsequent follow-up.

DISCUSSION

Mucormycosis is an opportunistic, life-threatening fungal infection that usually affects immunocompromised hosts. It is caused by fungi of the class Zygomycetes and order Mucorales.

Rhizopus oryzae is the most common cause of mucormycosis. Immunocompromised status and conditions associated with the increased availability of serum iron are other predisposing factors for mucormycosis.[1]

The hallmark of mucormycosis is angioinvasion with consequential systemic dissemination of the fungal spores, thrombosis of the affected blood vessels, and local tissue necrosis. Mucormycosis may be classified as rhinocerebral, pulmonary, cutaneous, gastrointestinal, disseminated, or miscellaneous. Rhinocerebral mucormycosis accounts for almost one-third to one-half of all cases. Mucormycosis of the gastrointestinal tract is rare.[3] Predisposing factors include malnutrition, especially in infants and children. Gastrointestinal mucormycosis is acquired by the ingestion of pathogens in foods such as fermented milk, dried bread products, and fermented porridge.[2] The stomach is the most common site of gastrointestinal mucormycosis, followed by the colon and ileum. However, contrary to this, in a recent study, it was found that intestinal disease may be emerging as the most common presentation. Furthermore, in a review of the cases categorized approximately by decade, before 2003, most cases were gastric cases, whereas among those included between 2003 and 2013, the vast majority were intestinal.[4]

The diagnosis of gastrointestinal mucormycosis is often delayed because of the nonspecific presentation. In the present case also, the patient did not present with guarding of abdominal muscles in spite of alarming intraoperative findings. This was probably due to immunosuppressed state due to uncontrolled diabetes resulting in masking of signs of peritonitis. Abdominal pain, distention, and vomiting are the most common presenting symptoms. The diagnosis is established by demonstrating characteristic broad, branching, and nonseptate hyphae in freshly infected tissues, usually in association with extensive angioinvasion, with resultant vascular thrombosis and infarction.

The treatment includes source control with surgical debridement and early antifungal therapy. Predisposing factors such as acidosis, hyperglycemia, deferoxamine, and immunosuppression should be addressed.[2] The antifungal agent of choice and most widely used is the lipid formulation of IV amphotericin B at 5 mg/kg daily. Posaconazole is used as step-down therapy for amphotericin responders or as salvage therapy for patients who cannot tolerate amphotericin or who do not respond. It is recommended that antifungal therapy should be continued until resolution of symptoms and signs, resolution or stabilization of radiographic abnormalities on serial imaging, and resolution of underlying immunosuppression.[5] It is important for clinicians to have a high index of suspicion for the diagnosis of intestinal mucormycosis as it can have a nonspecific presentation. An early diagnosis, prompt surgical intervention, and appropriate antifungal therapy are important for a favorable outcome.

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The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.