Clinical characteristics of tuberculosis in children in the north of Taiwan

Tuberculosis (TB) in children is an endemic and sometimes life-threatening disease in Taiwan. This study analyzed the clinical characteristics of a total of 112 children with TB managed in a referral children's hospital in the north of Taiwan between 1998 and 2002. The diagnosis of TB was made by either a positive result of culture, acid-fast stain, histopathology, or polymerase chain reaction (PCR). Tuberculin skin test was positive (indurations ≥10 mm) in 73% of 63 patients tested. The male-to-female ratio was 0.93 (54/58), and the mean age was 10.7 years. Thirty one percent of children were younger than 6 years of age, 12% were 6 to 12 years old, and 57% were older than 12 years. Fifty percent (50/100) of these children had household members with TB; 29.2% (31/106) were aboriginal; 93% had received Bacille Calmette-Guérin (BCG) vaccine. Isolated pulmonary TB was diagnosed in 65 cases (58%), extrapulmonary TB in 25 (22%), and combined intra- and extrapulmonary TB in 22 (20%). Fever was not a presenting symptom in 30.4% of children, was low grade (<38.5°C) in 23.2% and was high grade (≥38.5°C) in 46.4%. The mean duration of fever was 13.9 days. Patients with combined intra- and extrapulmonary TB had a significantly longer hospital stay (p<0.001), a higher peak body temperature (p<0.001), and a longer duration of fever (p=0.024). Patients with extrapulmonary TB had a significantly lower incidence of fever (p=0.001), a lower segment count (p=0.007) and a lower serum C-reactive protein level (p=0.019). Ventriculoperitoneal shunt insertion was performed in 8 of 12 cases with central nervous system involvement. Among 21 cases of TB osteomyelitis, tibia (33%) and spine (33%) were the most common sites of involvement. The overall mortality rate was 3.6% (4/ 112). Extrapulmonary TB and combined intra- and extrapulmonary TB were more commonly seen in children with a younger age and in those who had not received BCG vaccination. This study found that household members with TB history and aboriginal ethnicity were strongly associated with TB in Taiwanese children. Multidrug-resistant TB was uncommon in children born before the year 2003.