Follow up of a birth cohort to identify prevalence and risk factors for otitis media among Indian children in the eighth year of life.

BACKGROUND: Otitis media, a disease highly prevalent among children worldwide, manifests clinically in both acute and chronic forms. The manner and time at which chronicity develops among Indian children is unknown. AIM: To study the prevalence, manifestations and risk factors for otitis media in a birth cohort aged 8 years. METHODS: A birth cohort of 107 babies was followed up at 8 years of age and ENT evaluation with nasopharyngeal swabbing for detecting Streptococcus pneumoniae and Hemophilus influenzae was performed. RESULTS: The overall prevalence of otitis media was 14%, almost half the prevalence in the first 2 years of life. Eight children (7.5%) with congested, bulging eardrums and no systemic symptoms had asymptomatic acute otitis media. Another five (4.7%) children had otitis media with effusion and 2 (1.9%) had chronic suppurative otitis media. Although 10/15 (66.7%) children with otitis media had positive swabs at 8 years age, only 2 were pneumococcal vaccine (PCV-13) serotypes. Risk factor analysis showed that passive smoking was the only significant parameter associated with otitis media (p = 0.029). Nasopharyngeal swabbing showed that 51/105 (48.6%) children had positive swabs for S. pneumoniae and 5/105 (4.8%) for S.pneumoniae with non-type b H. influenzae. The ten most commonly encountered pneumococcal serotypes were 6A,4,8,16F,33B,35A,35B, 18C, 19F and 23B which together comprised 29 of the 56 (51.8%) isolates. PCV-13 serotypes formed 19/56 (33.9%) to 21/56 (37.5%) of all pneumococcal isolates. Of 6 children who had received PCV-13, 4 tested positive for S. pneumoniae at 8 years of age too. However, none were vaccine serotypes. Four of those with otitis media who had positive swabs had received no immunisation at all and 3 of them had vaccine serotypes, viz. 4, 6A and 18C respectively. CONCLUSION: Indian children continue to have a high prevalence of otitis media at 8 years age. More than 1/3 of nasopharyngeal isolates at this age are vaccine serotypes. Passive smoking is an important risk factor for childhood otitis media and may contribute to the development of chronicity of the disease.

High expression of S100 calgranulin genes in peripheral blood mononuclear cells from patients with Takayasu arteritis.

BACKGROUND: Toll-like receptors (TLR) 1 to 4 are highly expressed in aorta. Activation of TLR4 causes transmural arteritis in Human temporal artery-SCID chimera model. Neither TLR-4 nor its ligands have been studied in TA patients as yet. Aim of this study was to examine the expression of TLR4 and its endogenous ligands in peripheral blood mononuclear cells (PBMCs) of patients with Takayasu arteritis (TA). METHODS: mRNA expression of TLR4, RAGE and various endogenous TLR4 ligands were quantified in PBMCs of 24 TA patients and 19 sex and age matched healthy controls by real time PCR using specific primers and SYBR Green qPCR master mix. S100A8/A9 and S100A12 were measured in cell culture supernatant of PBMCs from TA patients and healthy controls, both in un-stimulated state as well as, after lipopolysaccharides (LPS) stimulated cultures for 4 h. Expression of S100A8/A9 in aortic tissues was assessed by immunohistochemistry. RESULTS: The mRNA expression of S100A8, S100A9, S100A12 and TLR4 were higher, while expression of RAGE and HSP70 were lower in TA as compared to healthy controls. Induction with LPS led to increase in secretion of both S100A8/A9 and S100A12 levels in TA as well as healthy controls. The fold of induction, measured by LPS stimulated/unstimulated control was higher in healthy controls [2.88 (1.7-3.53) fold] as compared to TA [1.345 (1-1.82) fold]; p < 0.05. Numerically, S100A8/A9 was also higher in healthy controls [2.04 (1.7-5.6) fold] as compared to TA [1.38 (1.09-3.6) fold], but it didn't reach statistical significance; p = 0.129. Mild to moderate intensity expression of S100A8/A9 protein was noted in aortic tissues from patients with TA. CONCLUSION: mRNA expression of TLR4 and its ligand S100A8, S100A9, and S100A12 in PBMCs of TA patients was higher as compared to healthy controls. LPS stimulation led to higher induction of S100A12 secretion in healthy controls as compared to TA. Expression of S100A8/A9 was detected in inflamed aortic tissues from patients with TA.