Supplementary Table S3.

Patients who were recommended topical antifungal treatment despite a negative eventual diagnosis of cutaneous fungal infection

Patient	Clinical suspicion group	Initial diagnosis and management before results of KOH smear	KOH Smear result	Eventual diagnosis and treatment	Rationale for continued use of topical antifungal
1	Low	Seborrhoeic dermatitis, to exclude tinea faciei. No empiric treatment with topical antifungal.	Negative	Seborrhoeic dermatitis	Treatment of seborrheic dermatitis
2	Low	Seborrhoeic dermatitis, to exclude pityrosporum folliculitis in a patient with human immunodeficiency virus infection who previously had pityrosporum folliculitis of the face. No empiric treatment with topical antifungal.	Negative	Seborrhoeic dermatitis	Treatment of seborrheic dermatitis
3	High	Tinea corporis, differential of irritant contact dermatitis. Empiric treatment with a combination cream of antifungal and steroid.	Negative	Eczema	The steroid component of the combination cream had resulted in adequate clinical response at the outpatient review. The same combination cream was continued in view of the patient’s preference to continue the same combination cream rather than to purchase a new steroid-only cream.
4	High	Tinea pedis, tinea manuum, tinea cruris. Empiric topical antifungal, with instructions to consider systemic antifungal if KOH smears positive.	Negative	Xerotic eczema	Given initial high clinical suspicion, after KOH smear result was available when the patient was still hospitalised, the dermatologist advised the inpatient primary physician to continue topical antifungal treatment despite the negative KOH smear. The final diagnosis was revised on outpatient review to xerotic eczema in view of poor response to topical antifungal-only cream. The negative KOH smear result in this case was therefore initially regarded as a false negative, but with the clinical monitoring and lack of response to topical antifungal, contributed to the revision of the patient’s eventual diagnosis.