Growth of lung parenchyma in infants and toddlers with chronic lung disease of infancy.
BACKGROUND
The clinical pathology describing infants with chronic lung disease of infancy (CLDI) has been limited and obtained primarily from infants with severe lung disease, who either died or required lung biopsy. As lung tissue from clinically stable outpatients is not available, physiological measurements offer the potential to increase our understanding of the pulmonary pathophysiology of this disease.


OBJECTIVE
We hypothesized that if premature birth and the development of CLDI result in disruption of alveolar development, then infants and toddlers with CLDI would have a lower pulmonary diffusing capacity relative to their alveolar volume compared with full-term control subjects.


METHODS
We measured pulmonary diffusing capacity and alveolar volume, using a single breath-hold maneuver at elevated lung volume. Subjects with chronic lung disease of infancy (23-29 wk of gestation; n = 39) were compared with full-term control subjects (n = 61) at corrected ages of 11.6 (4.8-17.0) and 13.6 (3.2-33) months, respectively.


RESULTS
Alveolar volume and pulmonary diffusing capacity increased with increasing body length for both groups. After adjusting for body length, subjects with CLDI had significantly lower pulmonary diffusing capacity (2.88 vs. 3.23 ml/min/mm Hg; P = 0.0004), but no difference in volume (545 vs. 555 ml; P = 0.58).


CONCLUSIONS
Infants and toddlers with CLDI have decreased pulmonary diffusing capacity, but normal alveolar volume. These physiological findings are consistent with the morphometric data obtained from subjects with severe lung disease, which suggests an impairment of alveolar development after very premature birth.
Balinotti
Juan E
JE
Department of Pediatrics, Indiana University Medical Center, James Whitcomb Riley Hospital for Children, 702 Barnhill Drive, Indianapolis, IN 46202-5225, USA.
Chakr
Valentina C
VC
Tiller
Christina
C
Kimmel
Risa
R
Coates
Cathy
C
Kisling
Jeffrey
J
Yu
Zhangsheng
Z
Nguyen
James
J
Tepper
Robert S
RS
D001997:Bronchopulmonary Dysplasia / Q000473:pathology* / Q000503:physiopathology; D016022:Case-Control Studies; D002908:Chronic Disease; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D011650:Pulmonary Alveoli / Q000254:growth & development* / Q000473:pathology* / Q000503:physiopathology; D011653:Pulmonary Diffusing Capacity