Objective: To describe a nosocomial outbreak of gastric mucormycosis caused by Rhizopus microsporus var. rhizopodiformis in five adult patients admitted to an intensive care unit (ICU).
Design: Epidemiological surveillance study.
Setting: A 12-bed polyvalent ICU of an acute care teaching hospital in Pamplona, Spain.
Patients: Five patients admitted to the ICU requiring artificial ventilation, diagnosis on admission severe pneumonia in four patients and one polytrauma patient, within a 14-week period, were diagnosed with gastric mucormycosis based on microbiological and/or histopathological characteristics. Upper gastrointestinal bleeding was the presenting manifestation in 80% of patients.
Interventions: Filamentous fungi isolated at the microbiology laboratory of the hospital were examined at the national Mycology Reference Laboratory in Madrid.
Measurements and results: Rhizopus microsporus var. rhizopodiformis growth was detected in gastric aspiration samples, environmental samples, wooden tongue depressors used to prepare oral medications (and given to patients through a nasogastric catheter), and in some tongue depressors stored in unopened boxes unexposed to the ICU environment. All depressors were purchased from the same supplier. R. microsporus was not isolated from batches purchased at different times from the same supplier and from another supplier. The outbreak terminated when contaminated tongue depressors were withdrawn from use.
Conclusions: Wooden tongue depressors contaminated by R. microsporus var. rhizopodiformis used to prepare oral medications caused an outbreak of fungal gastritis with an attributable mortality of 40%. Wooden material should not be used in the hospital setting.