Post-infectious bronchiolitis obliterans and mannose-binding lectin insufficiency in Argentinean children.
OBJECTIVE
Post-infectious bronchiolitis obliterans (PIBO) is a severe disorder following acute lower pulmonary infection in young children, especially caused by adenovirus. Mannose-binding lectin (MBL) deficiency arising from polymorphisms in the coding and non-coding region on the MBL2 gene has been associated with more frequent and severe respiratory infections. Our aim was to evaluate the influence of MBL variants in the susceptibility and evolution of children with PIBO.


METHODS
One hundred eleven children with PIBO diagnosis were studied. The coding A, B, D and X promoter variants of MBL2 gene were assessed by PCR-RFLP. B and D alleles were pooled as O. The combined genotypes A/A and YA/O were grouped as sufficient MBL (sMBL), and O/O and XA/O as insufficient MBL (iMBL) groups. To evaluate the frequency of MBL2 polymorphisms in the general population, we studied DNA samples from 127 healthy donors from the blood bank of the hospital (control group).


RESULTS
iMBL variants were significantly more frequent in PIBO children compared with controls (21.6% vs 10.2%, P = 0.01). PIBO patients with iMBL required intensive care unit (P = 0.001) and mechanical assistance at the moment of viral injury (P = 0.001) more frequently than those with sMBL.


CONCLUSIONS
Insufficiency of MBL was more common in PIBO children than in healthy controls. This genetic condition was significantly associated with more severe initial disease, illustrating the relevance of innate immune defence factors prior to the maturation of the adaptative immune system.
Pulmonology Department, Prof. Dr. Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina.
Verónica
V
Giubergia
Pulmonology Department, Prof. Dr. Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina.
Maximiliano
M
Salim
Biology Cellular and Retrovirus Laboratory, Prof. Dr. Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina.
Jesica
J
Fraga
Pulmonology Department, Prof. Dr. Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina.
Nicolás
N
Castiglioni
Biology Cellular and Retrovirus Laboratory, Prof. Dr. Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina.
Luisa
L
Sen
Pulmonology Department, Prof. Dr. Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina.
Claudio
C
Castaños
Biology Cellular and Retrovirus Laboratory, Prof. Dr. Juan P. Garrahan Pediatric Hospital, Buenos Aires, Argentina.|National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina.
Andrea
A
Mangano
D000293:Adolescent; D001118:Argentina / Q000453:epidemiology; D001989:Bronchiolitis Obliterans / Q000453:epidemiology* / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D004198:Disease Susceptibility; D005260:Female; D005787:Gene Frequency; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D037601:Mannose-Binding Lectin / Q000172:deficiency* / Q000235:genetics; D008661:Metabolism, Inborn Errors / Q000453:epidemiology* / Q000235:genetics; D011110:Polymorphism, Genetic; D012141:Respiratory Tract Infections / Q000150:complications
C445619:MBL2 protein, human; D037601:Mannose-Binding Lectin
children; mannose-binding lectin polymorphism; post-infectious bronchiolitis obliterans