title: Resistance patterns among multidrug-resistant tuberculosis patients in greater metropolitan Mumbai: trends over time.
abstract: BACKGROUND
  While the high burden of multidrug-resistant tuberculosis (MDR-TB) itself is a matter of great concern, the emergence and rise of advanced forms of drug-resistance such as extensively drug-resistant TB (XDR-TB) and extremely drug-resistant TB (XXDR-TB) is more troubling. The aim of this study was to investigate the trends over time of patterns of drug resistance in a sample of MDR-TB patients in greater metropolitan Mumbai, India.
  
  
  METHODS
  This was a retrospective, observational study of drug susceptibility testing (DST) results among MDR-TB patients from eight health care facilities in greater Mumbai between 2005 and 2013. We classified resistance patterns into four categories: MDR-TB, pre-XDR-TB, XDR-TB and XXDR-TB.
  
  
  RESULTS
  A total of 340 MDR-TB patients were included in the study. Pre-XDR-TB was the most common form of drug-resistant TB observed overall in this Mumbai population at 56.8% compared to 29.4% for MDR-TB. The proportion of patients with MDR-TB was 39.4% in the period 2005-2007 and 27.8% in 2011-2013, while the proportion of those with XDR-TB and XXDR-TB was changed from 6.1% and 0% respectively to 10.6% and 5.6% during the same time period. During the same periods, the proportions of patients with ofloxacin, moxifloxacin and ethionamide resistance significantly increased from 57.6% to 75.3%, from 60.0% to 69.5% and from 24.2% to 52.5% respectively (p<0.05).
  
  
  CONCLUSIONS
  The observed trends in TB drug-resistance patterns in Mumbai highlight the need for individualized drug regimens, designed on the basis of DST results involving first- and second-line anti-TB drugs and treatment history of the patient. A drug-resistant TB case-finding strategy based on molecular techniques that identify only rifampicin resistance will lead to initiation of suboptimal treatment regimens for a significant number of patients, which may in turn contribute to amplification of resistance and transmission of strains with increasingly advanced resistance within the community.
authors.affiliation: Jupiter Hospital, Thane, India.
authors.forename: Alpa
authors.initials: A
authors.lastname: Dalal
authors.affiliation: Vasant Vihar, Thane, India.
authors.forename: Akshay
authors.initials: A
authors.lastname: Pawaskar
authors.affiliation: Médecins Sans Frontières (MSF) / Doctors Without Borders, Mumbai, India.
authors.forename: Mrinalini
authors.initials: M
authors.lastname: Das
authors.affiliation: GTB Hospital, Sewri, Mumbai, India.
authors.forename: Ranjan
authors.initials: R
authors.lastname: Desai
authors.affiliation: Lilavati Hospital, Mumbai, India.
authors.forename: Pralhad
authors.initials: P
authors.lastname: Prabhudesai
authors.affiliation: Fortis Hospital, Mumbai, India.
authors.forename: Prashant
authors.initials: P
authors.lastname: Chhajed
authors.affiliation: Bhatia Hospital, Mumbai, India.
authors.forename: Sujeet
authors.initials: S
authors.lastname: Rajan
authors.affiliation: Observer Research Foundation, Mumbai, India.
authors.forename: Deepesh
authors.initials: D
authors.lastname: Reddy
authors.affiliation: L. H. Hiranandani Hospital, Mumbai, India.
authors.forename: Sajit
authors.initials: S
authors.lastname: Babu
authors.affiliation: Dr. D. Y. Patil Hospital, Navi Mumbai, India.
authors.forename: T K
authors.initials: TK
authors.lastname: Jayalakshmi
authors.affiliation: Médecins Sans Frontières (MSF) / Doctors Without Borders, Mumbai, India.
authors.forename: Peter
authors.initials: P
authors.lastname: Saranchuk
authors.affiliation: P.D. Hinduja National Hospital and Medical Research Centre, Mumbai, India.
authors.forename: Camilla
authors.initials: C
authors.lastname: Rodrigues
authors.affiliation: Médecins Sans Frontières (MSF) / Doctors Without Borders, Mumbai, India.
authors.forename: Petros
authors.initials: P
authors.lastname: Isaakidis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000995:Antitubercular Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D024901:Drug Resistance, Multiple, Bacterial; D005000:Ethionamide / Q000494:pharmacology; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology; D006801:Humans; D007194:India / Q000453:epidemiology; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D000077266:Moxifloxacin; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000302:isolation & purification*; D015242:Ofloxacin / Q000494:pharmacology; D057285:Precision Medicine; D012189:Retrospective Studies; D018088:Tuberculosis, Multidrug-Resistant / Q000145:classification / Q000453:epidemiology* / Q000382:microbiology*; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents; D024841:Fluoroquinolones; D015242:Ofloxacin; D005000:Ethionamide; D000077266:Moxifloxacin