Vinita Rane
Monash Health


Detection of Chlamydia trachomatis in Nasopharyngeal Specimens from Infants and Young Children: Is there a need for Routine Antenatal Screening?
Vinita Rane1, Kong Khailin1, Michelle Francis2, Despina Kotsanas1, Tony Korman1,2,3 and Maryza Graham1, 2
1Monash Health, Monash Medical Centre, 246 Clayton Road, Clayton VIC 3168
2Monash Pathology, 246 Clayton Road, Clayton VIC 3168
3Monash University, School of Medicine, Nursing and Health Sciences, Clayton VIC 3168

Aim:  Data to support routine antenatal screening for Chlamydia trachomatis (Ct) are currently lacking. We recently observed an increase in unexpected diagnoses of respiratory infections attributable to Ct in infants and young children that is likely maternally derived. In this study, we describe this case series and establish a case-detection rate for children less than one year old.

Method: From June 2015- June 2016, all nasopharyngeal aspirates/swabs (NPA) received for testing of respiratory viruses were tested with a new assay that included a gene target for Chlamydial species. For positive cases, Ct detection was confirmed with a second assay and we examined clinical characteristics of the child at the time of the NPA as well as maternal age. We also examined the detection rate of Ct compared to Respiratory Syncytial Virus (RSV), influenza A, influenza B, parainfluenzae and pertussis in children under the age of one year. 

Results: Over the study period, there were a total of 1114 NPA tested from children under age 1 year, with a pathogen detected in 618 (55%).  RSV was identified most commonly, with 327 (53%) positive samples. Parainfluenza 1,2 or 3 was detected in 64 (10%). Influenza A or B was detected in 30 (5%).  Ct was detected in 4 (1%) samples.  Maternal age was noted to be less than 25 years old for all cases.  In at least one case, the mother was found to have asymptomatic genitourinary Ct. Antenatal screening for Ct had not been performed in most cases.

Conclusions: These results suggest that unrecognized maternal Ct may lead to respiratory infection in their infants. Routine antenatal screening should therefore be considered for C. trachomatis, especially in women under the age of 25.