Disseminated Mucormycosis in Immunocompromised Children: Are New Antifungal Agents Making a Difference? A Multicenter Retrospective Study

Clinical Characteristics and Prognoses of Mucormycosis in Four Children

Background

Mucormycosis is a fatal invasive fungal infection that commonly affects immunocompromised children. The aim of our study was to investigate the clinical manifestations, treatments, and prognosis of pediatric patients with mucormycosis.

Methods

We conducted a retrospective search in Shenzhen Children's Hospital from July 2013 to July 2023 for all patients with mucormycosis. The clinical manifestation, pathogen detection, radiology, treatments, and prognosis were analyzed.

Results

Four cases were identified. Underlying conditions included acute myeloid leukemia with myeloid sarcoma (n = 1), thalassemia (post-allogeneic hematopoietic stem cell transplantation; n = 1), systemic lupus erythematosus (n = 1), and bilateral nephroblastoma (post-bilateral nephrectomy; n = 1). Two patients were disseminated mucormycosis, one case was pulmonary mucormycosis, and one case was cerebral mucormycosis. Fever, cough, and dyspnea were the main clinical symptoms of pulmonary mucormycosis, headache was the main clinical symptom of cerebral mucormycosis. Lung CT findings included consolidation, multiple nodules, halo sign, air crescent sign, and pleural effusion. The contrast-enhanced CT showed pulmonary artery and pulmonary vein occlusions in two patients and pseudoaneurysm in two patients. Amphotericin B formulations were administered as first-line therapy in all cases; in three cases, Triazole was administered in combination with amphotericin B.

Conclusion

Mucormycosis is a life-threatening disease involving multiple systems. Aorta pseudoaneurysm is a rare and fatal complication, enhanced CT can assist in diagnosis. Early diagnosis and appropriate therapeutic strategies are needed.

Overcoming the Odds: Successful Treatment of Disseminated Mucormycosis with Gastrointestinal and Jaw Involvement in a Patient with Acute Myeloid Leukemia

Disseminated mucormycosis is a rare life-threatening fungal infection that is uniquely seen in severely immunocompromised patients including those with hematological malignancies. We report a case of disseminated mucormycosis with a biopsy-proven gastrointestinal and oral cavity involvement in a patient with acute myeloid leukemia during induction chemotherapy. The patient had a successful outcome with limited resection of the involvement bowel segment, multiple maxillary dental extractions, debridement of the alveolus and hard palate, and combined antifungal therapy. After clinical improvement, stable infection on serial abdominal imaging, and completion of 6 weeks of combined antifungal therapy, consolidation chemotherapy was given, and molecular remission was achieved. The patient remained clinically well on secondary antifungal prophylaxis.

Part 1: Mucormycosis: Prevalence, Risk Factors, Clinical Features and Diagnosis

INTRODUCTION

Mucormycosis (MCR) is caused by filamentous molds within the Class Zygomycetes and Order Mucorales. Infections can result from inhalation of spores into the nares, oropharynx or lungs, ingestion of contaminated food or water, or inoculation into disrupted skin or wounds. In developed countries, MCR occurs primarily in severely immunocompromised hosts. In contrast, in developing/low income countries, most cases of MCR occur in persons with poorly controlled diabetes mellitus and some cases in immunocompetent subjects following trauma. Mucormycosis exhibits a propensity to invade blood vessels, leading to thrombosis and infarction of tissue. Mortality rates associated with invasive MCR are high and can exceed 90% with disseminated disease. Mucormycosis can be classified as one of six forms: (1) rhino-orbital-cerebral mucormycosis (ROCM); (2) pulmonary; (3) cutaneous; (4) gastrointestinal or renal (5); disseminated; (6) uncommon (focal) sites.

AREAS COVERED

The authors discuss the prevalence, risk factors and clinical features of mucormycosis.A literature search of mucormycosis was performed via PubMed (up to November 2022), using the key words: invasive fungal infections; mold; mucormycosis; Mucorales; Zyzomyces; Zygomycosis; Rhizopus, diagnosis.

EXPERT OPINION

Mucormycosis occurs primarily in severely immunocompromised hosts. Mucormycosis can progress rapidly, and delay in initiating treatment by even a few days worsens outcomes.

Invasive Fusariosis in Pediatric Hematology/Oncology and Stem Cell Transplant Patients: A Report from the Israeli Society of Pediatric Hematology-Oncology

Invasive Fusarium species infections in immunocompromised patients occur predominantly in those with hematological malignancies. Survival rates of 20−40% were reported in adults, but data in children are limited. Our retrospective, nationwide multicenter study of invasive fusariosis in pediatric hematology/oncology and stem cell transplant (SCT) patients identified twenty-two cases. Underlying conditions included hematological malignancies (n = 16; 73%), solid tumors (n = 2), and non-malignant hematological conditions (n = 4). Nineteen patients (86%) were neutropenic, nine (41%) were SCT recipients, and seven (32%) received corticosteroids. Sixteen patients (73%) had disseminated fusariosis, five had local infection, and one had isolated fungemia. Fifteen patients (68%) had skin involvement and eight (36%) had a bloodstream infection. Four patients (18%) presented with osteoarticular involvement and four with pulmonary involvement. Nineteen patients (86%) received combination antifungal therapy upfront and three (14%) received single-agent treatment. Ninety-day probability of survival was 77%: four of the five deaths were attributed to fusariosis, all in patients with relapsed/refractory acute leukemias. Ninety-day probability of survival for patients with relapsed/refractory underlying malignancy was 33% vs. 94% in others (p < 0.001). Survival rates in this largest pediatric population-based study were strikingly higher than those reported in adults, demonstrating that invasive fusariosis is a life-threatening but salvageable condition in immunosuppressed children.

New insights on mucormycosis and its association with the COVID-19 pandemic

COVID-19 continues to cause significant fatality worldwide. Glucocorticoids prove to play essential roles in COVID-19 management; however, the extensive use of steroids together with the virus immune dysregulation may increase the danger of secondary infections with mucormycosis, an angioinvasive fungal infection. Unfortunately, a definite correlation between COVID-19 and elevated mucormycosis infection cases is now clear worldwide. In this review, we discuss the historical record and epidemiology of mucormycosis as well as pathogenesis and associated host immune response, risk factors, clinical presentation, diagnosis and treatment. Special emphasis is given to its association with the current COVID-19 pandemic, including latest updates on COVID-19-associated mucormycosis cases globally, with recommendations for efficacious management.