Ophthalmological Manifestations of Infectious Embryo -Fetopathies at the Yaoundé Gyneco-Obstetric and Pediatric Hospital-Cameroon

Nomo AF^1,2*, Nyouma PJ³, Onoum Ekono OA¹, Nanfack NC^1,2, Mvilongo TC^1,3, Hassan A⁴, Akono Zoua Me^1,3, Nguefack S^1,2, Bella AL^1,2

¹Faculty of Medicine and Biomedical Sciences of Yaoundé, Cameroon
²Yaoundé Gyneco-Obstetric and Pediatric Hospital, Cameroon
³Yaoundé Central Hospital, Cameroon
⁴Faculty of Medicine and Pharmaceutical Sciences of Douala, Cameroon

*Correspondence author: Nomo Arlette Francine, Faculty of Medicine and Biomedical Sciences of the University of Yaoundé I, Cameroon and Yaoundé Gyneco-Obstetric and Pediatric Hospital, Cameroon; Email: nomoarlette2011@yahoo.fr 

Citation: Nomo AF, et al. Ophthalmological Manifestations of Infectious Embryo -Fetopathies at the Yaoundé Gyneco-Obstetric and Pediatric Hospital-Cameroon. J Ophthalmol Adv Res. 2025;6(3):1-13.

Copyright^© 2025 by Nomo AF, et al. All rights reserved. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Table 1: Distribution of patients according to age groups (n=20).

School-aged patients (≥ 3 years) represented 60% of the total sample. The proportion of children actually attending school was 16.6% (n=2).

Personal History

Prenatal History

The patients’ mothers were between 17 and 38 years old. Among them, 20% (n=4) were primiparous. Pregnancy monitoring began in the 2^nd trimester in 85% (n=17) of cases, in the 1^st trimester in 15% (n=3) and 20% (n=4) of the mothers had fewer than 4 ANC (antenatal care) visits. Regarding biological monitoring, 40% (n=8) of the mothers had not had serology for toxoplasmosis and rubella; 15% (n=3) of positive serology for toxoplasmosis during pregnancy were recorded, all carried out in the 2^nd trimester, including two positive serologies for IgG and one positive serology for IgM. No positive serology for rubella was found in the mothers’ pregnancy follow-up records. We found a mother who was seropositive for the Human Immunodeficiency Virus (HIV) and was undergoing antiretroviral treatment (Table 2).

Table 2: Distribution of patients according to prenatal history (n=20).

Perinatal History

90% (n=18) of the patients were born vaginally and 70% (n=14) were born at term. Birth Weights (BW) were normal in 80% (n=16); the mean BW was 2998 g ± 482.7 g [2000 g, 3800 g]. Head circumferences at birth were measured in 16 patients. The mean head circumference was 33.5 ± 3 cm [30 cm, 36 cm] (Table 3).

Table 3: Distribution of patients according to perinatal history (n=20).

Postnatal History

At birth, 40% (n=8) of patients received neonatal resuscitation and 62.5% (n=5) of them were hospitalized for neonatal asphyxia.

The neonatal hospitalization rate was 40% (Fig. 1).

Figure 1: Distribution of children according to outcomes after childbirth.

History of Immuno -Allergic Disorders

None of the patients were HIV-positive and the Expanded Program on Immunization (EPI) vaccination follow-up was up to date for their age for each of them.

General Clinical Characteristics

Initial Symptoms

The mean age at onset of clinical signs was 5.7 ± 5 months [0, 24] months. Psychomotor developmental delay was the most common disorder, occurring in 85% (n=17), followed by microcephaly in 50% (n=10) of cases (Table 4).

Table 4: Distribution of patients according to general clinical signs (n=20).

The most frequently encountered ophthalmological sign was BAV in 40% (n=8) of cases (Table 5).

Table 5: Distribution of patients according to ophthalmological clinical signs (n=20).

CT Scan Lesions

tomography was performed in 85% (n=17) of cases. Parenchymal calcifications were the main CT scan finding in 70.5% (n=12) followed by cortical atrophy in 41.1% (n=7) (Fig. 2).

Figure 2: Distribution of patients according to scanographic signs.

Neurological and Sensory Sequelae

A proportion of 75% (n=15) of the patients were being treated for chronic conditions, most often cerebral palsy (n=14) and one case of autism. The treatment initiated in 60% (n=9) of them was antiepileptic drug-based medication. An optical correction prescription was noted in 10% (n=2) of patients.

Etiologies

Based on clinical and paraclinical findings, the diagnosis was directed towards a specific pathogen in 45% of cases. CMV infection was the most frequent (25%) (Table 6).

Table 6: Distribution of patients according to etiology (N=20).

Data from the Current Ophthalmological Examination

Functional Signs

Decreased Visual Acuity (DVA) was observed in 8 patients, followed by strabismus and ptosis (3 patients) (Fig. 3).

Figure 3: Distribution of patients according to ophthalmological functional signs.

Clinical Signs

Of the 40 eyes examined, ophthalmological manifestations were observed in 18 eyes, representing 45% (12 patients) of the study population. Among these patients, 54.5% (n=6) had binocular disorders. For 10% (n=2) of the population, we observed blindness but no structural abnormality in the ophthalmological examinations performed chorioretinitis scars (4 eyes), microphthalmia (3 eyes) (Fig. 4).

Figure 4: Distribution of eyes according to ophthalmological manifestations.

Of the 20 patients examined, cooperation was obtained with only 2 patients.

• Visual Acuity Assessment

Cooperative patient group (02) had useful distance visual acuity (> 3/10). In the non-cooperative patients, we assessed light tracking: 12 out of 40 eyes did not track the light.

• Eyelid Examination

Eyelid abnormalities were found in 9 eyes, the most frequent being small palpebral fissures and ptosis (3 eyes) (Fig. 5).

Figure 5: Distribution of anomalies in the annexes.

Anterior Segment Examination

Anterior segment abnormalities were observed in 6 eyes: microcornea (3 eyes), 2 partial cataracts (2 eyes) and one bilateral iris coloboma (Table 7).

Table 7: Distribution of eyes according to anterior segment anomalies (N=40).

Examination of the Posterior Segment

Fundus examination of four eyes could not be performed due to the inaccessibility of the posterior segment. Abnormalities were found in seven eyes and chorioretinitis scarring was observed in four eyes (Table 8).

Table 8: Distribution of eyes according to posterior segment anomalies (N=36).

Discussion

Sample Size

From January 1, 2017, to December 31, 2021, a period of 5 years, we enrolled 20 patients with infectious embryo-fetopathy. In 2012, Saghrouni, et al., identified 21 cases of congenital toxoplasmosis in Tunisia over an 11-year period (from 2000 to 2011) [18]. In Switzerland, in 2019, Huillier, et al., obtained a sample of 39 patients with congenital toxoplasmosis over a 33-year study period (from 1982 to 2015) [19]. Jin, et al., in 2017, obtained 237 patients with congenital CMV infection over a 31-year period [15]. Lahbil, et al. In 2007, they obtained a sample of 26 patients with congenital ocular rubella over a 4-year period (2001 to 2005) [20]. Lu, et al., in 2016, obtained a sample of 45 patients with symptomatic TORCH embryo-fetopathy with congenital cataract [21].

The sample sizes in these studies are larger than ours. This could be explained by the shorter duration of our study compared to those of many of them. Furthermore, these studies indicate that infectious embryo-fetal diseases are rare conditions.

Epidemiological Characteristics

Sex

According to data from the literature, embryofetopathies affect boys and girls in varying proportions. Thus, in our series, males were predominant (55%), with a sex ratio of 1.2. This result was similar to that of Jin, et al., who had a sex ratio of 1.2 [15]. In 2005, Garweg, et al., also found a sex ratio of 1.2 in patients with ocular manifestations of congenital toxoplasmosis in France [22]. However, this result differs from that of Lahbil, et al., who had 56.25% female sex in the study population of patients with congenital rubella, for a sex ratio of 0.7 [20]. In 2016, Lu, et al., found a sex ratio of 0.9 in patients with congenital cataracts due to TORCH infections [21].

Age

The mean age in our series was 39 months ± 25 months. The most represented age group was 24 to 60 months. This result is close to that of Lu, et al., who reported a mean age of 19.57 months ± 22.16 months [21]. The fact that the first clinical signs generally appear during the first year of life could explain the young age of the patients [23].

School Enrollment Rates

The proportion of school-aged patients (≥ 3 years) was 60%. Among them, 16.6% were enrolled in school. This result can be explained by the fact that 75% of our study population suffered from chronic neurological conditions with impaired language acquisition and age-appropriate social interaction. Cerebral palsy was the most common.

Personal History

Pregnancy monitoring began in the second trimester in 85% of cases and in the first trimester in 15%. Among these women, 20% had fewer than four prenatal visits (ANC). Regarding biological monitoring, 40% of mothers had not undergone serological testing for toxoplasmosis and rubella. This could be due to some mothers not understanding the importance of ANC for healthy pregnancies, nor the importance of TORCH infection screening. This could be explained by a lack of awareness about the consequences of these infections. Added to this is certainly the lack of financial resources in a context where there is no universal health coverage Among the serologies performed, a proportion of 15% were positive for toxoplasmosis during pregnancy, all carried out in the 2^nd trimester, including two positive serologies for IgG and one positive serology for IgM . The late performance of the toxoplasmosis serologies could justify the predominance of IgG serology compared to IgM. Indeed, since IgM are markers of an active infection, vertical transmission of the germ would probably have occurred in the 1st trimester of pregnancy, the period most associated with fetal malformations [24].

Of the 20 patients seen, 70% were born at term. In the 2013 study by Townsend, et al., on congenital CMV infections in the UK, there was a higher proportion of patients born at term (94%) [23]. Birth weights were normal in 80% of cases, with a mean birth weight of 29,987 g ± 482.7 g. This result is similar to that of Jin, et al., who found a mean birth weight of 2,820 g ± 804 g [15]. Neonatal asphyxia was the most frequently reported reason for hospitalization (25%). These cases were probably due to acute fetal distress and gynecological causes.

Neurological and Sensory Sequelae

Seventy-five percent of patients were being treated for chronic conditions, most often cerebral palsy (n=14). This condition is very frequently associated with psychomotor delay [13,25]. In 2019, in a study conducted at HGOPY, Nguefack, et al., demonstrated that cerebral palsy was found in 92.7% of patients with psychomotor delay [26] . One case of autism was reported. The association between CMV and autistic disorders has been suspected for years. However, the role of CMV in the development of autistic disorders remains to be clarified [27]. The prevalence of congenital CMV was 5.3% among children with autistic disorders [27]. Optical correction was prescribed for 10% of patients. The patients concerned by these prescriptions had strabismus, for which optical correction is a treatment of choice [28]. However, we noted that the patients were not compliant with this treatment. Their children’s restlessness was the main reason given by the parents for not adhering to the corrective lens-wearing protocol.

Etiologies

In our sample, CMV infection was the most frequent (25%). This result is consistent with the literature, which describes CMV as the most common cause of congenital infection [10]. Similarly, while they had only 39 cases of congenital toxoplasmosis in Switzerland between 1982 and 2015, Huillier, et al., found a similar number of cases of congenital CMV, 38 in total, in 2017 alone [19]. Diagnostic uncertainty was observed in 55% of cases. This could be explained by fact that CMV and HSV 1 and 2 serology are not routinely requested during pregnancy monitoring.

General Clinical Characteristics

Initial Symptomatology

The mean age at onset of clinical signs was 5.7 ± 5 months. This result is consistent with that of Townsend, et al., for whom all moderate and severe sequelae of congenital CMV infection were apparent during the first year of life [23]. Psychomotor developmental delay was the most frequently observed disorder (85%), followed by microcephaly (50%). Numerous neurological manifestations of infectious embryo-fetopathies have been described in the literature. Lahbil, et al., reported that 31.25% of their study population had psychomotor delay and 12.5% had microcephaly [20]. Whereas Jin, et al., found 35.2% and 54.3% respectively for psychomotor delay and microcephaly [15].

Nevertheless, our results are superior to those of these studies. This could be explained by the fact that, as the patients were selected from the pediatric department of HGOPY, more specifically from neuropediatrics, the majority of the first signs encountered were neurological in nature. The most common ophthalmological sign was decreased visual acuity in 40% of cases, most often the absence of eye tracking, a sign that quickly raises parental concern. In 2010, in a study on bilateral blindness and low vision in children at HGOPY, Bella, et al., found that the conditions were primarily intrauterine (41.8%), including infectious embryo-fetopathies [17].

CT Scan Lesions

Among the additional tests requested for etiological investigation, cerebral computed tomography was performed in 85% of cases. The literature has shown that since its introduction, cerebral computed tomography has been widely used for the diagnosis of congenital CMV infections, not only to detect CNS lesions, but also to establish the prognosis [86]. Intracranial calcifications were the main radiological finding in 70.5% of cases. This result is not far from that of Garweg, et al., found intracranial calcifications in 96% of patients with neuro-ocular manifestations of congenital toxoplasmosis [22]. Among them, 16% had CT scan images of cortical atrophy. In contrast, Saghrouni, et al., showed that intracranial calcifications were the most common anomaly with a frequency of 14.28% but with a rate lower than ours [18].

In 2018, Kwak, et al., reported that the occurrence of developmental delay is significantly correlated with the presence of polymicrogyria, Ventriculomegaly, calcifications and white matter involvement have also been described [31].

Current Ophthalmological Examination

In 90% of patients, we were unable to assess visual acuity. Our population included many infants and children with cerebral palsy, some of whom had delayed speech and comprehension difficulties. Consequently, cooperation was not obtained. In our series, in the evaluation of monocular light tracking, 30% of the eyes did not follow the light. This result is higher than that of Jin, et al., who found a 10% rate of absence of light pursuit [15] . This difference could be explained by the fact that, unlike the patients in their series, most of our patients did not have ophthalmological follow-up. Consequently, many lesions had the opportunity to worsen.

We found two cases of strabismus. Strabismus is a common sign in congenital toxoplasmosis and CMV infection. According to Coats, et al., strabismus was observed in 12 of 42 (29%) symptomatic patients [27]. Jin, et al., found 25.2% of patients with strabismus in a series of 186 patients with congenital CMV [15]. Garweg, et al., reported 16% of patients with strabismus among those with ocular involvement in congenital toxoplasmosis [22]. Microphthalmia was found in 7.5% of the eyes examined. This result is close to that of Garweg, et al., who found 5.4% of patients with microphthalmia, as well as in that of Saghrouni, et al., who had 9.5% microphthalmic patients [18,22]. In contrast, Lahbil, et al., found 40.6% microphthalmia in a population of patients with congenital rubella [20] . Thus, congenital rubella appears to be a stronger cause of microphthalmia.

In our series, we found two cases of unilateral partial cataracts. In 2020, Domngang,  et al., in a study on congenital cataracts in a hospital setting in Mbalmayo, reported 10.2% of cases due to congenital rubella [32]. Furthermore, toxoplasmosis has been implicated in the occurrence of congenital cataracts, as in the case report by Eballe, et al., who described a case at HGOPY in 2010 [33].

Lu, et al., found 45 cases of congenital cataracts with positive TORCH serology, of which 57.7% were due to CMV and 31.1% to HSV types 1 and 2 [21]. In the literature, cataracts are identified as the main ocular manifestation of congenital rubella [2]. Thus, in a series of 16 patients with congenital rubella, Lahbil, et al., found 25 eyes (78.1%) with congenital cataracts [20].

Microcornea was observed in three cases in our series. We note that they were all associated with microphthalmia. The iris malformation observed in our series was a bilateral iris coloboma. This malformation was also described by Lahbil, et al., chorioretinitis scarring and optic atrophy are ocular manifestations that have been described many times [20]. In 2018, Capretti, et al., described, in a population of 48 children with symptomatic CMV infection, 39% of visual sequelae diagnosed in the neonatal period, primarily retinal scarring [34].

Coats, et al., found that visual impairment in patients with congenital CMV infection was mainly due to optic atrophy in 6 out of 16 eyes (37%) and macular scarring in 2 out of 16 eyes (13%) [27]. Garweg, et al., of 430 patients with congenital toxoplasmosis, 130 (30.2%) had chorioretinitis and 2 cases of optic atrophy [22]. Jin, et al., reported 12.9% of retinal lesions due to chorioretinitis and 4.3% of optic atrophy [15].

We also described a whitish vitreous mass in one eye that required further investigation as the diagnosis was uncertain. It could have been a retinoblastoma, a persistent hyaloid membrane or another entity [20]. In 10% of the population, we observed blindness but no structural abnormalities on ophthalmological examinations. Despite the lack of investigation, damage to the visual cortex in the occipital lobe is a possibility. Cortical visual impairment was found in 8 out of 16 eyes (50%) by Coats, et al., [27].

Limitations of the Study

It was difficult for us to definitively identify the pathogens responsible for the various lesions observed both clinically and paraclinically. Furthermore, TORCH serological tests were not performed in a timely manner and follow-up was not conducted for positive cases. The patients’ lack of cooperation due to their neurological disabilities limited the performance of certain ophthalmological examinations, particularly visual acuity assessment and intraocular pressure measurement. The unavailability of electrophysiological tests rendered the description of some of the abnormalities found incomplete. We were unable to provide images from examinations of the posterior segment of the eye. Moreover, children often require sedation for retinal photography, but the necessary equipment was not available in the ophthalmology department.

Conclusion

This study revealed that the most frequently implicated pathogen in embryofetopathies was CMV. Psychomotor developmental delay was the most common neurological disorder, while decreased visual acuity was the most frequent ophthalmological sign. Ophthalmological manifestations were observed in 45% of the study population, the most frequent being chorioretinitis scars (10%) and microphthalmia (7.5%). Systematic screening from the first trimester of pregnancy is necessary through TORCH serology testing. Regular ophthalmological follow-up is necessary, including a multidisciplinary approach.

Conflict of Interest

The author declares no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Funding Details

No funding was received for this review.

Author’s Contributions

All authors have contributed equally to this work and have reviewed and approved the final manuscript for publication.

Consent For Publication

Not applicable.

Ethical Statement

Not Applicable.

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