title: Massive posterior fossa tuberculous abscess developing in a young child treated for miliary tuberculosis. Possible role of very rapid acetylation of isoniazid.
abstract: A 21-month-old infant presented with acute obstructive hydrocephalus due to a large tuberculous abscess in the posterior fossa 3 months after starting treatment for miliary tuberculosis. Insertion of a ventriculo-peritoneal shunt resulted in some clinical improvement but subsequent neurological deterioration occurred due to massive enlargement of the tuberculous abscess despite apparently adequate antituberculosis therapy. Repeated drainage procedures of the abscess eventually resulted in resolution and clinical improvement. As part of the workup for poor weight gain and the unusual clinical course, the patient's acetylation status for isoniazid was determined and found to be very rapid. Doubling the daily dose of isoniazid was followed by a dramatic weight increase and further clinical improvement. Decreasing the load of tuberculous antigen by draining the abscesses and increasing the pulse exposure of isoniazid is the best possible explanation for the clinical improvement finally seen in this patient.
authors.affiliation: Department of Paediatrics and Child Health, University of Stellenbosch and Tygerberg Hospital, Tygerberg, Republic of South Africa.
authors.forename: J F
authors.initials: JF
authors.lastname: Schoeman
authors.forename: A
authors.initials: A
authors.lastname: Morkel
authors.forename: H I
authors.initials: HI
authors.lastname: Seifart
authors.forename: D P
authors.initials: DP
authors.lastname: Parkin
authors.forename: P D
authors.initials: PD
authors.lastname: Van Helden
authors.forename: R H
authors.initials: RH
authors.lastname: Hewlett
authors.forename: P R
authors.initials: PR
authors.lastname: Donald
mesh_terms: D000038:Abscess; D000107:Acetylation; D000995:Antitubercular Agents / Q000378:metabolism* / Q000627:therapeutic use; D001922:Brain Abscess / Q000209:etiology* / Q000382:microbiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology; D007223:Infant; D007538:Isoniazid / Q000378:metabolism* / Q000627:therapeutic use; D014391:Tuberculosis, Miliary / Q000150:complications* / Q000188:drug therapy / Q000378:metabolism / Q000601:surgery
chemical_list: D000995:Antitubercular Agents; D007538:Isoniazid