[Infants 12 month-old or less as a high risk group in tuberculosis--comparison of clinical data with those in children aged one to two years].
A number of tuberculosis (TB) infants 12 month-old or less is larger than the ones of any other age groups with childhood TB in our hospital. This study was undertaken to elucidate clinically why infants 12 month-old or less suffered from TB most among infants and early children. We studied tuberculin skin reaction, isolation frequency of Mycobacterium tuberculosis (MTB) in gastric aspirates, and frequency of systemic dissemination of TB among 45 TB infants 12 month-old or less, and compared the results with those of 31 control TB infants and children aged 13 to 35 month-old. The frequency distribution of tuberculin skin reaction size among the studied infants was significantly smaller than that among the controls (p < 0.05). MTB was positive among 33 out of the 45 studied infants (73%) while 12 out of the 31 controls (39%), and the difference was significant (p < 0.005). Miliary TB and/or TB meningitis were seen among 8 out of the 45 studied infants (18%) while 1 out of the 31 controls (3%), and there was marginally significant difference between them (p = 0.054). These results suggest that delayed-type hypersensitivity and cell-mediated immunity to MTB among infants 12 month-old or less may be lower than those among infants and children aged 13 to 35 month-old, and the studied infants may be inferior in their capacity to kill mycobacteria and to encapsulate mycobacteria by granuloma formation.
Kondo
S
S
Division of Respiratory Disease, Tokyo Metropolitan Children's Hospital.
Ito
M
M
Kageyama
S
S
D002675:Child, Preschool; D003953:Diagnosis-Related Groups / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007111:Immunity, Cellular / Q000276:immunology; D007223:Infant; D008297:Male; D012306:Risk; D014374:Tuberculin Test; D014376:Tuberculosis / Q000175:diagnosis* / Q000276:immunology