Severe conidiobolomycosis complicating induction chemotherapy in a patient with acute lymphoblastic leukaemia

Human Pathogenic Entomophthorales

The pathogenic entomophthoralean fungi cause infection in insects and mammalian hosts. Basidiobolus and Conidiobolus species can be found in soil and insect, reptile, and amphibian droppings in tropical and subtropical areas. The life cycles of these fungi occur in these environments where infecting sticky conidia are developed. The infection is acquired by insect bite or contact with contaminated environments through open skin. Conidiobolus coronatus typically causes chronic rhinofacial disease in immunocompetent hosts, whereas some Conidiobolus species can be found in immunocompromised patients. Basidiobolus ranarum infection is restricted to subcutaneous tissues but may be involved in intestinal and disseminated infections. Its early diagnosis remains challenging due to clinical similarities to other intestinal diseases. Infected tissues characteristically display eosinophilic granulomas with the Splendore-Höeppli phenomenon. However, in immunocompromised patients, the above-mentioned inflammatory reaction is absent. Laboratory diagnosis includes wet mount, culture serological assays, and molecular methodologies. The management of entomophthoralean fungi relies on traditional antifungal therapies, such as potassium iodide (KI), amphotericin B, itraconazole, and ketoconazole, and surgery. These species are intrinsically resistant to some antifungals, prompting physicians to experiment with combinations of therapies. Research is needed to investigate the immunology of entomophthoralean fungi in infected hosts. The absence of an animal model and lack of funding severely limit research on these fungi.

Experimental infection in gerbils by Conidiobolus lamprauges

Conidiobolomycosis is an emerging entomophthoramycosis caused by fungi Conidiobolus spp. Animal models are essential for the study of infectious disease in various areas such as pathogenesis, diagnostic methods, treatment and prevention. There is not currently an animal model for conidiobolomycosis. The aim of this study was to create an experimental infection protocol for Conidiobolus lamprauges in gerbils (Meriones unguiculatus). The study animals were randomly divided into four groups of four animals: immunosuppressed with cyclophosphamide (CPA) and infected with C. lamprauges (G1), immunocompetent and infected with C. lamprauges (G2), immunosuppressed with CPA (G3), and an immunocompetent control group (G4). Clinical signs were observed only in G1 animals, where the mortality rate reached 75% by day 7 after infection (AI) with a median survival of 2 days. C. lamprauges was detected only in G1, both by PCR and by isolation. Necropsies of the G1 animals showed lesions in the nasal cavity and lung tissue. These lesions were characterized by polymorphonuclear infiltrate cells and by the presence of hyphal structures under silver staining. This animal model will be useful for further investigation of diseases caused by C. lamprauges, particularly of those associated with immunosuppression factors in naturally occurring animal infections.

In vitro susceptibility of Conidiobolus lamprauges recovered from sheep to antifungal agents

Data regarding the susceptibility of Conidiobolus lamprauges is limited and there is no consensus about the optimal treatment for infections caused by Conidiobolus spp. In this context, the objective of this study was to evaluate the in vitro susceptibility of six C. lamprauges strains isolated from sheep conidiobolomycosis to amphotericin B, ketoconazole, fluconazole, itraconazole, posaconazole, voriconazole, anidulafungin, caspofungin, micafungin, flucytosine, and terbinafine using the CLSI M38-A2 microdilution technique. Terbinafine was the most active (MIC range <0.06-0.5 μg/mL). Resistance or reduced susceptibility was observed for amphotericin B and azole and echinocandin antifungals. Additional studies are necessary to determine the therapeutic potential of terbinafine as monotherapy or in combination therapy with other antifungals.

Conidiobolomycosis in a young Malaysian woman showing chronic localized fibrosing leukocytoclastic vasculitis: a case report and meta-analysis focusing on clinicopathologic and therapeutic correlations with outcome

BACKGROUND

Conidiobolomycosis (also known as rhinoentomophthoramycosis) is a rare cutaneous/mucosal fungal infection seen mainly in the tropical rain forest regions of the world that can be associated with disfiguring facial elephantiasis, and rarely, death.

OBJECTIVE

To present an exemplary case report and perform a systematic review of the world's literature to more accurately describe the natural history and the effect of therapy on outcome in conidiobolomycosis.

METHODS

Case report and meta-analysis of published case reports and series of conidiobolomycosis to determine which clinical, pathologic, mycologic, and treatment factors impact on prognosis.

RESULTS

We document delay in diagnosis of conidiobolomycosis in a young Malaysian woman, whose biopsy showed pathognomonic features-massive tissue eosinophilia and Splendore-Hoeppli phenomenon surrounding broad hyphae. These findings coexisted with granuloma faciale-like changes (fibrosing leukocytoclastic vasculitis) and lymphedema. Treatment with multiple antifungals was followed by complete resolution. For the meta-analysis, pooled data from 199 cases (162 with full outcome data) from 120 reports revealed a similar course for most cases: a disease affecting healthy young adults who present with progressive nasal symptoms (eg, nasal obstruction) and central facial swelling and show improvement or cure after surgical excision and/or treatment with one or more antifungal agents in 83%. Persistent-progressive facial disease occurred in 11%, and 6% died rapidly of fungal infection. Presentation with facial elephantiasis correlated with persistent-progressive rhinoentomophthoramycosis and a longer duration of disease before diagnosis (P = 0.02). Lethal infections were significantly associated with nonstereotypical presentation (eg, orbital cellulitis), visceral infection, absence of the Splendore-Hoeppli phenomenon, presence of comorbidities (eg, immunosuppression, hematolymphoid malignancy), infection with Conidiobolus incongruus or Conidiobolus lamprauges (not Conidiobolus coronatus), lack of response to amphotericin B, and female sex (all P ≤ 0.002). The few sensitivity studies performed demonstrated in vitro multidrug resistance of Conidiobolus species to most available antifungal agents.

LIMITATIONS

Publication bias, reporting heterogeneity, and data deficits may affect results.

CONCLUSIONS

Conidiobolomycosis should be included in the differential diagnosis of patients who present with nasal symptoms and painless centrofacial swelling. Massive tissue eosinophilia and Splendore-Hoeppli material coating thin-walled hyphae confirms the clinical diagnosis. The granuloma faciale-like histology found in this case can explain the onset of facial lymphedema by fibroinflammatory destruction of lymphatic vessels; the duration of disease and severity of inflammation likely predicts whether the lymphedema is reversible or not. Although rhinoentomophthoramycosis ostensibly responds in vivo to most available antifungal agents, routine culture and susceptibility testing is recommended to better define the efficacy of these therapeutic agents.

Conidiobolomycosis in relapsed acute lymphoblastic leukemia

Invasive fungal infections in immunocompromised children suffering from hematological malignancies have been a major cause of morbidity and mortality. In recent years fungi other than aspergillus and candida are gaining importance. These emerging fungal infections have distinct epidemiological features and management issues especially in immunocompromised patients. Here we report the isolation of Conidiobolus coronatus, a rarely reported zygomycetes infection in a patient suffering from acute lymphoblastic leukemia. Conidiobolus generally causes indolent infection in the sino-respiratory tract. They are known to be angioinvasive and can disseminate. There is no consensus regarding appropriate antifungal treatment for Conidiobolus infection.

Zygomycetes infections in pediatric hematology oncology patients: a case series and review of the literature

Fungi from the Zygomycetes class are increasingly recognized causes of infection in immunosuppressed children, but no comprehensive literature review and few case series have been published on the topic. A case series of 6 pediatric oncology patients with Zygomycetes infections cared for at our institution was constructed, and a concurrent search of the English language literature for Zygomycetes infections in children with oncologic disorders was undertaken. Our case series described 6 patients (5 male) between the ages of 2.5 and 19.5 years. One patient was diagnosed with rhinocerebral disease, 2 with rhinosinusitis, 2 with pulmonary involvement, and 1 with a gastrointestinal presentation. Five patients survived. Our literature review identified 82 cases from 61 studies. The mean subject age was 10.8 years (1.4 to 21.0 y). About 92.7% of all patients suffered from some form of leukemia, with 70.7% suffering from acute lymphoblastic leukemia. Overall, 58.5% of reported patients survived, with individuals with disseminated disease showing the worst prognosis (68.2% mortality) and those with cutaneous disease the best (14.3% mortality). Survival is increasingly reported in the literature, perhaps as a result of improved diagnostic capabilities, increased physician awareness and increased reliance on adjunctive surgical therapy.