Title of Case(s):

What it comes from wetlands

Background:

Scalp infections are usually due to bacteria or fungus and can be common in children. The approach to diagnosis in more severe presentations must take account geographic features and outdoor activities of the patient.

Case Presentation Summary:

A previously healthy 7-year-old girl presented with a 7cm wide, painful, edematous plaque on the vertex, with adherent yellowish scales, peripheral pustules, and a deep, large ulcer with undermined borders and purulent discharge (fig 1). She had this lesion for 2 months but in the last week she complained of general malaise, had fever and exhibited cervical lymphadenopathy. The mother recalled that it biggened with several nodular lesions that ultimately ulcerated with drainage.

She had just arrived from a rural and wetland area of Brazil, where she had close contact with soil as her family were farmers and had a domestic cat.

The patient was already with oral amoxicillin for one week, without improvement, which prompted admission for inpatient care.

Multi-resistant Pseudomonas aeruginosa and methicillin-susceptible Staphylococcus aureus were isolated from the purulent discharge, and therefore intravenous cefepime was prescribed. As the clinical suspicion of kerion was high, fluconazole was added. Later, polymerase chain reaction identified Sporothrix schenkii in the purulent discharge¸ and antifungal treatment was changed to itraconazole. Finally, Tricophyton mentagrophytes was isolated in the mycological culture of perilesional hairs.

The child was discharged 3 weeks later with clinical improvement, maintaining oral itraconazole for an additional 4 months, at which point complete resolution was observed followed by progressive hair growth.

Key Learning Points:

Sporotrichosis is a subacute/chronic infection, endemic in tropical areas, caused by the dimorphic geophilic fungi Sporothrix schenckii, which is a common saprophyte of soil. The transmission can also be zoonotic, mainly by infected cats. This case had an invaluable contribution from molecular biology for the establishment of a correct and complete diagnosis.