Congenital toxoplasmosis and audiological outcome: from a case series to a suggestion of patient-based schedule

Introduction

Sensorineural hearing loss (SNHL) has been suggested to be possibly related to congenital toxoplasmosis (CT), although its prevalence varies from 0% to 26%. This variance appears to be dependent especially on early timing of treatment. However, the available data are based on outdated studies conducted on small groups of patients that lack homogeneity. Therefore, to establish evidence-based guidelines for audiologic monitoring in CT, we conducted a comprehensive evaluation of a large case series over a long period of time.

Patients and methods

This is a single-center, retrospective cohort that enrolled all infants and children who were exposed in utero to Toxoplasma gondii and/or congenitally infected between September 1980 and December 2022. They underwent standard serial audiological evaluations to detect possible SNHL at an early stage. The first evaluation was performed during the initial assessment to define the onset of congenital toxoplasmosis, with another evaluation conducted at least at 12 months of life.

Results

We collected data from 1,712 patients, and 183 (10.7%) were diagnosed with CT. Among these cases, 78 children (42.6%) presented with symptomatic CT at the onset, exhibiting ocular findings (21.1%), clinical cerebral manifestations (6.1%), and/or abnormal findings on neuroimaging (35.5%). Therapy was administrated at the onset in 164 patients (89.6%) with 115 of them starting treatment prior to 2.5 months of age (0-388, median 32.00 ± 92.352 days of life). Only one patient presented with SNHL at the onset, but this was apparently unrelated to CT. The median number of audiological assessments was 2.2 ± 1.543 (2-10). No patients developed any grade of delayed hearing loss, both in treated and untreated groups. The median age at last audiological evaluation was 2.3 ± 2.18 years (1-8), although the median follow-up period was 12.4 years (±6.3), ranging from 1 to 27 years.

Conclusions

Based on these data, it appears that SNHL may be less frequent in CT than previously assumed. We recommend conducting an audiological assessment at the onset (within the first 2.5 months of life) to comprehensively define the type of CT onset, and then conducting another evaluation within 9 months of life.

Congenital cytomegalovirus infection: the state of the art and future perspectives

Congenital cytomegalovirus (cCMV) infection is the most common congenital infection, with an estimated incidence of approximately one in 200 infants in high-income settings. Approximately one in four children may experience life-long consequences, including sensorineural hearing loss and neurodisability. Knowledge regarding prevention, diagnosis, and treatment increased in the recent years, but some challenges remain. In this review, we tried to summarize the current knowledge on both the obstetrical and pediatric areas, while also highlighting controversial aspects and future perspectives. There is a need to enhance awareness among the general population and pregnant women through specific information programs. Further research is needed to better define the classification of individuals at birth and to have a deeper understanding of the long-term outcomes for so defined children. Finally, the availability of valaciclovir medication throughout pregnancy, where appropriate, has prompted the assessment of a universal serological antenatal screening. It is recommended to establish a dedicated unit for better evaluation and management of both mothers and children.