EpistemisAnal itching due to pinworms
Specialty: Gastrointestinal.
Why it occurs
- Active nocturnal migration of females of the nematode Enterobius vermicularis towards the perianal and perineal region to deposit their eggs, triggering a local allergic reaction mediated by the mucilaginous secretion that surrounds them.
Initial workup
Transparent adhesive tape test (Graham Test: morning application of an adhesive tape to the perianal region before bathing for three consecutive days, for subsequent observation under the microscope in search of characteristic Enterobius eggs) | Direct nocturnal visual inspection of the perianal area (visualization of small white filiform parasites measuring 8-13 mm).
red flags
Bacterial superinfection secondary to intense scratching of the perianal area (erysipelas or rapidly progressive perineal cellulitis), appearance of local microabscesses, or suppurative vulvovaginitis in young girls due to aberrant migration of the parasite.
Standard management
- Mebendazole — 100 mg orally in a single dose, compulsorily repeated after two weeks to eradicate the larvae that have hatched after the first dose; It is mandatory to treat all cohabitants simultaneously
- Albendazole — 400 mg orally in a single dose, repeated after two weeks
- Mild local emollients or zinc oxide ointment (to soothe perianal skin irritation secondary to scratching).
Educational guidance for study. It is NOT a prescription recommendation. The actual choice depends on the cause, the patient, and current guidelines.
- Area
- Gastrointestinal
- Listed causes
- 1
- Treatment options
- 3