Results
Sixty contacts were identified. Of 16 children, 11 were placed on RIF/PZA. Five did not return for treatment despite repeated efforts. Of 29 adults with LTBI, 23 were placed on RIF/PZA, 3 did not return for therapy and could not be located, and 3 were treated with 4 months of rifampin. Rifampin was used because one person was treated by another health department and two returned for treatment several months after this outbreak.
The majority of children (64%) were born in the United States. Mean age was 6 years (range, 0.75 to 15 years). The adults with LTBI were a young, healthy group of recent immigrants. All were born in Mexico. Fifty-nine percent were male and mean age was 27 years (range, 17 to 50). No adults or children reported comorbidities; none were known to be HIV infected. Fifty-nine percent of the adults reported alcohol use before treatment. Although all adults were employed, none had health insurance.
Ten of 11 children completed 2 months of RIF/PZA,with few side effects (Table 1). One child, age 15,developed asymptomatic drug-induced hepatitis (ALT 216 U/L on day 25 of treatment), and RIF/PZA was suspended. Only 13 of 23 adults completed RIF/PZA treatment. Four adults were diagnosed with hepatitis between days 10 and 53, and RIF/PZA was suspended (Table 2). Once their liver enzymes normalized, two completed 4 months of rifampin, making the overall completion rate 65%. There were no associated hospi-talizations or deaths.
The four adults with hepatotoxicity had higher daily doses of pyrazinamide than those without (1365 mg v 948 mg, p=0.02). There were no significant differences in alcohol use, age, gender, or comorbidities. Three of the four adults with hepatotoxicity had serologic testing for hepatitis; none had evidence of acute hepatitis A,hepatitis B surface antigen, or hepatitis C antibody. All four denied drinking during treatment.
Estimated cost of an uncomplicated course of RIF/PZA was $219 per adult, compared to $122 for 4 months of rifampin. The health department needed additional funding to pay for RIF/PZA and blood draws. Health department employees reported linguistic and cultural barriers to treatment and monitoring.Additional Spanish interpreters and providers were hired to ensure communication about potential hepa-totoxicity. The health department also had to address contacts’ belief that giving blood every 2 weeks would“drain them of energy” (MRC). This strongly held belief made timely monitoring difficult. Many of the adults did not keep appointments and came to the clinic at unexpected times. It is not clear if this was due to cultural factors or patients’ work schedules. Health department employees felt that “it was challenging to follow the guidelines that recommend intensive monitoring for hepatitis.”