TUBERCULOSIS SUSCEPTIBILITY PATTERNS, PREDICTORS OF MULTIDRUG-RESISTANCE, AND IMPLICATIONS FOR INITIAL THERAPEUTIC REGIMENS AT A NEW-YORK-CITY HOSPITAL
Ac. Weltman et Dn. Rose, TUBERCULOSIS SUSCEPTIBILITY PATTERNS, PREDICTORS OF MULTIDRUG-RESISTANCE, AND IMPLICATIONS FOR INITIAL THERAPEUTIC REGIMENS AT A NEW-YORK-CITY HOSPITAL, Archives of internal medicine, 154(19), 1994, pp. 2161-2167
Background: Multidrug resistance has complicated tuberculosis therapy.
We studied antibiotic susceptibilities of Mycobacterium tuberculosis
and predictors of multidrug resistance to assist in determining initia
l drug regimens. Methods: We conducted a case-control study based on c
hart review of patients with and without multidrug resistant tuberculo
sis, including outpatients and inpatients with culture-proved tubercul
osis seen at a large New York, NY, hospital during 1991 and 1992. Pati
ent characteristics studied included serologic findings for human immu
nodeficiency virus and the presence of the acquired immunodeficiency s
yndrome. Descriptive analysis considered potential initial drug regime
ns. A theoretically effective regimen was assumed to contain at least
two drugs to which an isolate was susceptible. Results: For 172 patien
ts, 28.5% of isolates were resistant to isoniazid, at least 20.9% to r
ifampin, 15.7% to ethambutol, 8.1% to pyrazinamide, 18.6% to streptomy
cin, 9.9% to ethionamide, 8.1%preomycin, cycloserine, and ciprofloxaci
n; 18.6% were resistant to both isoniazid and rifampin. Chart review o
f 159 patients showed that acquired immunodeficiency syndrome, human i
mmunodeficiency virus seropositivity, female gender, residence in the
Bronx, and race were associated with multidrug resistance. The four-dr
ug regimen of isoniazid, rifampin, ethambutol, and pyrazinamide was th
eoretically effective for 81% to 85% of patients. No subset of patient
s would have a markedly better theoretical benefit from that regimen.
Only five- or six-drug regimens that used the combinations of capreomy
cin plus ciprofloxacin, capreomycin plus cycloserine, ciprofloxacin pl
us cycloserine, or all three drugs together theoretically offered sign
ificantly higher effectiveness. Conclusions: Tuberculosis isolates at
our hospital have a high frequency of multidrug resistance. Only five-
or six-drug regimens are theoretically adequate as initial therapy fo
r our patients. to kanamycin, and none to ca