Background Invasive fungal infections such as Mucormycosis are considered opportunistic infections that occur almost exclusively in immunosuppressed patients, causing high morbidity and mortality. The use of long-term steroids may favour the state of immunosuppression, increasing the likelihood of acquiring this type of severe infections. The errors of therapeutic compliance are one of the possible causes of long-term treatment with corticosteroids.

Purpose The aim of the study was to discuss, through a clinical case, the consequences of an error in compliance with corticosteroid therapy.

Material and methods Observational, retrospective and descriptive case report of a patient diagnosed with mucormycosis due to the inappropriate use of corticoids. The data were obtained by review of the electronic clinical history (JARA) and the pharmacy service managing software (FARMATOOLS).

Results The patient was a 47 years’ old male with a clinical history of arterial hypertension, dyslipaemia, morbid obesity, with smoking and alcoholic habits. In August 2018, he was operated on for an acute subdural haematoma. After being discharged from the hospital, the doctor prescribed Dexamethasone 4 mg every 12 hours, descending gradually. Due to the patient’s misunderstanding, he kept the same medication dose (8 mg Dexamethasone daily) and did not comply with the gradual withdrawal of the medication. Fifty days’ later, the patient was admitted to hospital with acute hepatitis, necrotising fasciitis in the right lower limb after trauma and intense palate pain. Suspecting mucormycosis and bacterial infection, the patient was treated with the empirical treatment: liposomal Amphotericin B, Isavuconazole, Daptomycin, Amikacin and CLindamycin. The presence of Rhizopus spp. was confirmed and invasive rhinosinusal mucormycosis secondary to immunosuppression due to the continued dose of corticosteroids was diagnosed. Finally, the patient died nine days after hospital admission due to multiorgan failure.

Conclusion In this case, the main cause of the development of mucormycosis came from a medication error in corticosteroid therapy compliance. Aiming to improve this kind of medication error, it is important to highlight the need to enhance pharmacotherapeutic monitoring, information and education for patients with the aim of improving therapeutic compliance.

References and/or acknowledgements Acknowledgements to the maxillofacial and oral surgery departments and the intensive care department.

No conflict of interest.