Gastrointestinal mucormycosis: A periodic systematic review of case reports from 2015 to 2021

Gastrointestinal and Intra-Abdominal Mucormycosis in Non-Haematological Patients-A Comprehensive Review

Intra-abdominal and gastrointestinal mucormycosis are less frequent than rhino-orbito-cerebral and pulmonary mucormycosis, but highly lethal. Their diagnosis remains challenging due to the non-specific clinical presentation. We collected English-language cases of intra-abdominal and gastrointestinal mucormycosis in non-haematological and non-neonatal patients published up to October 2024. This review analysed the epidemiological, clinical, and therapeutic charts of 290 cases. A proportion of 53.4% were reported from India and the USA. The main predisposing conditions were diabetes, solid organ transplant, ICU, and corticosteroid treatment. The most common site was the stomach (53.8%). Gastrointestinal perforation, skin breakdown, and abdominal wall infection were sources of intra-abdominal localisation. The most common symptoms were abdominal pain, vomiting, and gastrointestinal bleeding. The diagnosis relied on histology (93.8%), mycology with microscopy and culture (38.8%), and molecular methods (9.9%). Mortality (52.9%) was lower when treatment was intravenous amphotericin B, combined or not with surgery. Prompt treatment, essential for a favourable outcome, relies on early suspicion and diagnosis. Gastrointestinal and intra-abdominal mucormycosis should also be suspected in patients admitted in ICU with ventilation/nasogastric tube and corticosteroids and those with abdominal trauma or surgery, presenting abdominal distension, pain, and GI bleeding. Mycological diagnosis including direct examination, culture and Mucorales qPCR on tissue should assist with rapid diagnosis and thus treatment.

Mucormycosis

Mucormycosis is an aggressive and frequently lethal disease. Most patients with mucormycosis have poorly controlled diabetes mellitus and rhino-orbito-cerebral disease. Patients with hematologic malignancy and transplant recipients mostly present with rhino-orbito-cerebral or pulmonary disease. Prompt recognition of clinical symptoms and radiographic features of mucormycosis is required to establish timely diagnosis and initiate targeted therapy. Diagnosis is, historically, made by direct microscopy, culture, and pathology of biopsy tissue, but molecular methods are increasingly playing a role in establishing an earlier diagnosis. Treatment is multidisciplinary, involving early surgical intervention, antifungal therapy, and correction of underlying immune compromising risk factors when possible.

Epidemiological Trends of Mucormycosis in Europe, Comparison with Other Continents

Mucormycosis is an invasive fungal infection, caused by fungi of the order Mucorales, and it is associated with high morbidity and mortality. The epidemiology of mucormycosis is evolving. The incidence, underlying risk factors, clinical presentation, as well as the responsible mucoralean agents, vary by geographic region. The estimated incidence in developed countries ranges from less than 0.06 to 0.3 cases per 100,000 population per year, while in India, it reaches approximately 14 cases per 100,000 population per year, which is about 80 times higher. In European countries the estimated incidence ranges from less than 0.04 to 0.12 per 100,000 population per year. Diabetes mellitus (DM) is the leading underlying disease globally. In Europe, hematological malignancies are the most common risk factor for mucormycosis, while in Asia diabetes predominates. The rhino-cerebral form of mucormycosis is most commonly seen in patients with DM, whereas pulmonary mucormycosis in patients with hematological malignancies and transplants. The most common species globally is Rhizopus arrhizus, whereas new emerging species only occasionally cause infection in Europe. However, vigilance is required, as they may raise concerns-especially in light of climate change- due to their potential to cause serious infections in both immunocompetent and immunosuppressed individuals.

Venous intestinal ischemia of fungal origin as a cause of intestinal obstruction in immunocompromised patients: case report and literature review

BACKGROUND

Mucormycosis is a highly lethal opportunistic fungal disease caused by ubiquitous molds of the order Mucorales, with Rhizopus, Lichtheimia and Mucor being the most common genera. This rare disease primarily affects immunocompromised patients, with presentations ranging from rhino-orbito-cerebral infections to disseminated mucormycosis with angioinvasion, leading to thrombosis and tissue infarction. Gastrointestinal mucormycosis is the least common clinical presentation and is believed to be secondary to spore ingestion. It can involve multiple components of the gastrointestinal tract, such as the stomach, liver, ileum, and colon, with nonspecific manifestations, including pain, nausea, vomiting, and abdominal distension. The initial clinical presentation may even manifest as gastrointestinal bleeding due to gastric ulceration or intestinal perforation.

CASE PRESENTATION

Here we present the case of a 48-year-old male patient with a 9-year history of human immunodeficiency virus (HIV) infection who was hospitalized in the context of febrile neutropenia and whose acute respiratory infection was documented; therefore, antibiotic treatment was initiated. However, due to persistent febrile peaks and peripheral blood showing documentation of multilineage cytopenias, a bone marrow biopsy was performed, compatible with presenting features of marrow myelodysplasia. During hospitalization, the patient presented left flank abdominal pain, and an abdominal computed tomography (CT) scan revealed signs of intussusception of a small bowel loop at the distal jejunum level, leading to intestinal obstruction with ischemic progression, requiring ileectomy (60 cm). Histopathological analysis of the resected intestine revealed severe transmural ischemic changes associated with venous thrombosis due to fungal structures, with histochemical studies demonstrating the presence of zygomycete (Mucor) fungal structures, leading to the initiation of treatment with amphotericin B. However, despite treatment, the patient experienced progressive clinical deterioration with persistent fever and ventilatory failure, with follow-up tests showing absolute neutropenia and blood cultures positive for yeast, leading to death 52 days after admission.

CONCLUSIONS

The diagnosis of intestinal mucormycosis may be delayed due to the lack of specificity of the signs and symptoms. Pathologists as well as histopathological studies are essential for timely treatment.

A rare intestinal mucormycosis caused by Lichtheimia ramosa in a patient with diabetes: a case report

Mucormycosis is an aggressive fungal disease. Gastrointestinal mucormycosis is rare, but its clinical symptoms lack specificity and mortality is high. Here, we report a case of intestinal mucormycosis caused by Lichtheimia ramosa in a 65-year-old woman with diabetes mellitus. The patient exhibited extensive mucosal tissue damage in the colon, with broad, undivided filamentous fungal hyphae present in the intestinal tissue. Therefore, the patient was suspected to have a filamentous fungal infection. Colonic tissue samples were obtained for fungal culture, and the fungus was identified as L. ramosa based on morphology and DNA sequencing. This case highlights the importance of pathologists and microbiologists in identifying pathogenic fungi and the significance of screening for mucormycosis in high-risk patient populations.

Idiopathic aplastic anemia with concurrent complications of colonic perforation and mucormycosis: Case report

We report a case of a 72-year-old female who presented with fever, abdominal pain, and diarrhea accompanied by leukopenia, anemia, and thrombocytopenia. The diagnosis of acute aplastic anemia was confirmed through bone marrow aspiration. Treatment included glucocorticoids, immunoglobulin therapy, and plasma exchange. Subsequently, the patient developed gastrointestinal bleeding and abdominal Computed Tomography (CT) revealed perforation of the transverse colon. Pathological examination of surgically removed diseased tissue confirmed mucor infection. Despite receiving antifungal therapy with amphotericin B, the patient's condition deteriorated due to the sepsis progression. Mucor infection in immunocompromised patients should be vigilant, and early diagnosis may help improve prognosis.

Angioinvasive gastrointestinal mucormycosis with duodenal necrosis and perforation in a patient with visceral myopathy

A 55-year-old woman with a past medical history of visceral myopathy with multiple resultant abdominal surgeries, colectomy caused by severe pseudo-obstruction, and end-stage renal disease on hemodialysis presented with complaints of nausea, abdominal distention, vomiting, and diarrhea for five days. Small-bowel obstruction was identified on CT. She subsequently developed acute gastrointestinal bleeding, anemia, and hemodynamic instability. Extensive gastric ulceration with frank hemorrhage prompted urgent subtotal gastrectomy with multiple intraoperative findings, including a necrotic distal duodenum. Surgical pathology showed invasive fungal infection of the duodenum with perforation, morphologically compatible with invasive mucormycosis. The patient was started on intravenous liposomal amphotericin B, but despite best efforts, the patient ultimately succumbed to this invasive fungal infection in addition to sepsis and multi-organ failure.

From Spores to Solutions: A Comprehensive Narrative Review on Mucormycosis

Mucormycosis is an infrequent but fatal illness that mainly affects patients with uncontrolled diabetes mellitus, diabetic ketoacidosis, solid and hematologic neoplasms, organ transplantation, chronic steroid intake, prolonged neutropenia, iron overload states, neonatal prematurity, severe malnutrition, and HIV. Many cases were reported across the world recently following the COVID-19 pandemic. Recent research has led to a better understanding of the pathogenesis of the disease, and global guidelines are now available for managing this serious infection. Herein, we comprehensively review the etiological agents, pathogenesis, clinical presentations, diagnosis, and management of mucormycosis.

Epidemiology, Modern Diagnostics, and the Management of Mucorales Infections

Mucormycosis is an uncommon, yet deadly invasive fungal infection caused by the Mucorales moulds. These pathogens are a WHO-assigned high-priority pathogen group, as mucormycosis incidence is increasing, and there is unacceptably high mortality with current antifungal therapies. Current diagnostic methods have inadequate sensitivity and specificity and may have issues with accessibility or turnaround time. Patients with diabetes mellitus and immune compromise are predisposed to infection with these environmental fungi, but COVID-19 has established itself as a new risk factor. Mucorales also cause healthcare-associated outbreaks, and clusters associated with natural disasters have also been identified. Robust epidemiological surveillance into burden of disease, at-risk populations, and emerging pathogens is required. Emerging serological and molecular techniques may offer a faster route to diagnosis, while newly developed antifungal agents show promise in preliminary studies. Equitable access to these emerging diagnostic techniques and antifungal therapies will be key in identifying and treating mucormycosis, as delayed initiation of therapy is associated with higher mortality.

Disseminated Invasive Mucormycosis Infection Following Autologous Stem Cell Transplantation for Diffuse Large B-Cell Lymphoma

Invasive fungal infections (IFI) are challenging to predict, diagnose and treat, and are associated with a particularly high mortality among patients with hematological malignancies. They are relatively uncommon in patients with lymphoma, compared with those with acute leukemia or undergoing allogeneic transplantation. We present a patient, autografted for recurrent lymphoma, with fever and refractory diarrhea persisting post engraftment, eventually attributable to disseminated mucor infection. This case illustrates the challenge of timely diagnosis and initiation of treatment for IFI in lymphoma patients, who do not routinely receive antifungal prophylaxis, and the importance of aggressive investigation and symptom-directed tissue sampling for evidence of IFI in febrile immunocompromised hosts not responding to broad-spectrum antibiotics.

Clinical presentations, diagnosis, management, and outcomes of renal mucormycosis: An overview of case reports

Background

Renal mucormycosis (RM) is a rare presentation of invasive mucormycosis with a high mortality rate. There is no single systematic review of the literature that indicates the different clinical aspects of RM.

Methods

A systematic search of PubMed/Medline was performed to collect individual case reports of RM in patients of all ages published between 2010 and April 2022.

Results

Seventy-one individual cases were detected through PubMed bibliographic database searches, with a final assessment performed on 60 patients with RM. India and Asia had the largest number of reported cases, with 30 (50%) and 42 (70%) reports, respectively. Also, 74 and 26% of the patients with a mean age of 33 years were male and female, respectively. RM showed 44% mortality rate in the analyzed cases. Immunosuppressive agent therapy followed by tissue transplantation (kidney and liver) and diabetes were the most remarkable risk factors in patients. Nevertheless, 22% of the patients were immunocompetent with no apparent underlying condition. COVID-19 positivity was detected in eight adult patients with an 87% mortality rate. The most common signs of infection were fever, flank pain, and oliguria; additionally, isolated RM was reported in 57% of the cases. In 55% of the patients, histopathologic examination alone was sufficient to diagnose RM, whereas molecular methods and culture were used in only 18 and 35% of patients, respectively. Surgery alone, surgery plus anti-infection therapy, and anti-infection therapy alone were used in 12, 60, and 13% of patients, respectively. Furthermore, 15% of the patients died before any treatment.

Conclusion

The early diagnosis of RM is necessary. In this regard, the use of molecular-based diagnostic assays can help identify the fungus at the genus and species levels and use an appropriate treatment in the shortest possible amount of time. Because of the increase in antibiotic resistance in recent years, determining microbial susceptibility tests can lead to the better infection management. Additionally, withdrawal of immunosuppressant, appropriate surgical intervention, and antifungal therapy are the main factors associated with a successful outcome in RM.

COVID-19 and Intestinal Ischemia: A Multicenter Case Series

Introduction

Gastrointestinal symptoms are common among COVID-19 patients. Although gastrointestinal involvements are mostly benign, they rarely indicate a severe pathology like intestinal ischemia. The present case series describes 21 patients with bowel ischemia, necrosis, or perforation.

Methods

The present case series was conducted from April 2020 to February 2022 in the surgical wards of two Iranian hospitals. We retrospectively included adult patients with concomitant COVID-19 and intestinal ischemia. Primary outcomes were defined as the length of stay and survival.

Results

Twenty-four patients with a median age of 61.5 years were included in the study. Sixteen (67%) patients were male, and 13 (54%) were without any comorbidities. Macrovascular mesenteric ischemia was not identified in 21 patients (87.5%). Gastrointestinal manifestations appeared on the median of seven days (range 2–21) after the diagnosis of COVID-19, with the most common symptom being abdominal pain. All the patients had a significantly elevated C-Reactive Protein prior to surgery, ranging from 68 to 362. D-dimer was measured in eight patients and was significantly elevated, ranging from 1,878 to over 5,000 ng/mL. One patient was managed conservatively due to a good clinical condition. Except for one patient with angioinvasive mucormycosis and one other with leukocytoclastic vasculitis, pathologic evaluation revealed general features of intestinal necrosis, including ulcer, hemorrhage, necrosis, neutrophilic infiltration (in seven patients), neutrophilic abscess (in four patients), and edema. Bowel necrosis accompanied mortality of 15 (62.5%) patients and a median of 6.5 days of hospital stay.

Conclusion

Intestinal ischemia in COVID-19 patients is associated with a high mortality rate. Further research is needed to elucidate the dynamics of intestinal ischemia in the setting of COVID-19.