title: Computed Tomography-Guided Biopsy for Potts Disease: An Institutional Experience from an Endemic Developing Country.
abstract: METHODS
  A retrospective chart review.
  
  
  OBJECTIVE
  In endemic resource poor countries like Pakistan, most patients are diagnosed and treated for Potts disease on clinical and radiological grounds without a routine biopsy. The purpose of this study was to evaluate the use and effect of computed tomography (CT)-guided biopsy in the management of Potts disease since the technique is becoming increasingly available.
  
  
  BACKGROUND
  CT-guided biopsy of spinal lesions is routinely performed. Literature on the utility of the technique in endemic resource poor countries is little.
  
  
  METHODS
  This study was conducted at the Neurosurgery section of Aga Khan University Hospital Karachi. All the patients with suspected Potts disease who underwent CT-guided biopsy during the 7 year period from 2007 to 2013 were included in this study. Details of the procedure, histopathology and microbiology were recorded.
  
  
  RESULTS
  One hundred and seventy-eight patients were treated for suspected Potts disease during the study period. CT-guided biopsies of the spinal lesions were performed in 91 patients (51.12%). Of the 91 procedures, 22 (24.2%) were inconclusive because of inadequate sample (10), normal tissue (6) or reactive tissue (6). Sixty-nine biopsies were positive (75.8%). Granulomatous inflammation was seen in 58 patients (84.05%), positive acid-fast bacillus (AFB) smear in 4 (5.7%) and positive AFB culture in 12 patients (17.3%). All 91 cases in which CT-guided biopsy was performed responded positively to antituberculosis therapy (ATT).
  
  
  CONCLUSIONS
  75.8% of the specimens yielded positive diagnoses. Granulomatous inflammation on histopathology was the commonest diagnostic feature. In this series, the rates of positive AFB smear and culture were low compared to previous literature.
authors.affiliation: Section of Neurosurgery, The Aga Khan University Hospital, Karachi, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Waqas
authors.affiliation: Section of Neurosurgery, The Aga Khan University Hospital, Karachi, Pakistan.
authors.forename: Mohsin
authors.initials: M
authors.lastname: Qadeer
authors.affiliation: Section of Neurosurgery, The Aga Khan University Hospital, Karachi, Pakistan.
authors.forename: Faizuddin
authors.initials: F
authors.lastname: Faiz
authors.affiliation: Section of Neurosurgery, The Aga Khan University Hospital, Karachi, Pakistan.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Alvi
authors.affiliation: Section of Neurosurgery, The Aga Khan University Hospital, Karachi, Pakistan.
authors.forename: Muhammad Ehsan
authors.initials: ME
authors.lastname: Bari
keywords: Aspiration biopsy; Computed tomography; Potts disease