Cutaneous Mucormycosis Due to Rhizopus oryzae in Immunocompromised Pediatric Patient
Authors: Viridiana Enríquez García Estrella , Elena Martínez Bustamante María 
Published: November 2023

Abstract

Introduction
Mucormycosis is an infection predominantly in immunocompromised patients by fungi of the Mucorales order, the most frequent being Rhizopus spp., Mucor spp. and Lichteimia spp. Characterized by vascular invasion, necrosis in the lung, CNS, paranasal sinuses, gastrointestinal system, and skin.

Case Presentation
2-year-old female patient, native and resident of Valle de Chalco, State of Mexico. Recent diagnosis of B lineage acute lymphoblastic leukemia, in remission induction phase. Medical/surgical history: December 10 2021: Bone marrow aspirate -January 10 2022: Remission induction chemotherapy with vincristine and daunorubicin -January 17 2022: Central venous catheter placement -Family history: Parents are reported healthy. Positive drug addiction for smoking. They have two doses of vaccine for SARS COV2 -Epidemiologic history: Protective isolation was indicated in this patient -Allergies, rash, transfusion and traumatic: Denied -Adequate nutrition, adequate hygiene, complete vaccination schedule. Neurodevelopment according to age -Hospitalized on January 17 for fever and neutropenia, treatment with fourth-generation cephalosporin as initial management. -On January 20, 2022, she presented an erythematousviolaceous papular lesion, raised in the center, without central necrosis, without elevation, and painful on palpation on the right forearm -Treatment with fourth generation cephalosporin and glycopeptide was started, a biopsy culture of the lesion was taken and Central and peripheral blood cultures -On physical examination, an erythematous-violaceous maculopapular lesion was observed on the right forearm, without necrosis, without exudate and painful on palpation. Vital Signs in normal ranges.

Relevant labs
Leukopenia was found with profound neutropenia and thrombocytopenia. Positive acute phase reactants, with positive procalcitonin and C-reactive protein.

Final Diagnosis
For the study of the tissue, debridement of the wound, samples of the spindle center and external edges for biopsy and Lactophenol cotton blue staining were performed. Final diagnosis is Cutaneous Mucormycosis. The culture reports Rhizopus oryzae. For treatment, start Liposomal Amphotericin B 5 milligrams per kilogram per dose every 24 hours. It was increased to 10 milligrams per kilogram per dose for progression of the lesion.

Teaching Points
Mucormycosis is produced by opportunistic fungi of the order Mucorales. It presents an acute and fatal course that requires early diagnosis and treatment to avoid complications and death (1) A timely diagnosis is very important, since with surgical and antifungal treatment the survival rate increases to 70% (2) Isavuconazole showed activity against mucormycosis with efficacy similar to Amphotericin B. Isavuconazole can be used for the treatment of mucormycosis and is well tolerated (3,4).

References
1. Quiroz, N; Villanueva JP; Lozano, EA. Mucormicosis. Rev Asoc Colomb Dermatol. 2017; 25 : 4 (octubre - diciembre), 284-293
2. Zimmermann N, Hagen MC, Schrager JJ, Hebbeler-Clark RS, Masineni S. Utility of frozen section analysis for fungal organisms in soft tissue wound debridement margin determination. Diagn Pathol. 2015 Oct 15;10:188.
3. Marty FM, Ostrosky-Zeichner L, Cornely OA, Mullane KM, Perfect JR, Thompson GR 3rd, et all; VITAL and FungiScope Mucormycosis Investigators. Isavuconazole treatment for mucormycosis: a single-arm open-label trial and case-control analysis. Lancet Infect Dis. 2016
4. Cornely OA, et al. Global guideline for the diagnosis and management of mucormycosis: an initiative of the European Confederation of Medical Mycology in cooperation with the Mycoses Study Group Education and Research Consortium. Lancet Infect Dis. 2019 Dec;19(12):e405-e421
We would like to thank the PRINCIPAL network for technical support and for funding to attend this conference