Seronegative ocular toxoplasma panuveitis in an immunocompetent patient

Coinfection of Ocular Toxoplasmosis and Ocular Toxocariasis in the Same Patient

PURPOSE

To report a rare case of a toxoplasma chorioretinitis in one eye and peripheral ocular toxocariasis granuloma in the fellow eye of the same patient.

MATERIALS AND METHODS

Retrospective case report.

RESULTS

A 44-year-old male presented with gradual loss of vision over the past weeks. The patient was diagnosed with ocular toxoplasma chorioretinitis recurrence in his right eye and an inactive peripheral granuloma of ocular toxocariasis was found in the left eye. The patient was a farmer who had been involved in animal husbandry throughout his life. The patient was treated with antibiotics for toxoplasma chorioretinitis and kept under follow-up for ocular toxocariasis.

CONCLUSION

Coinfections of zoonoses are related to socioeconomic environment and individual characteristics of the host. Ocular toxoplasmosis and ocular toxocariasis may present with different scenarios. To our knowledge, this is the first case of a coinfection of ocular toxoplasmosis and ocular toxocariasis in the same patient. A thorough ophthalmological examination and detailed anamnesis are important for diagnosis.

Prevalence of Toxoplasmic Retinochoroiditis in an Australian Adult Population: a Community-Based Study

OBJECTIVE

Toxoplasmic retinochoroiditis is the most common clinical manifestation of an infection with the protozoan parasite, Toxoplasma gondii. Up to 50% of the human population is estimated to be infected with T. gondii. However, the epidemiology of toxoplasmic retinochoroiditis is not widely reported. We sought to estimate the prevalence of toxoplasmic retinochoroiditis in Australia using data collected as part of the Busselton Healthy Ageing Study.

DESIGN

Cross-sectional, community-based, prospective cohort study.

PARTICIPANTS

5,020 Australian adults (2,264 men and 2,756 women; age range of 45-69 years and median age of 58 years).

METHODS

Retinal color photographs centered on the optic disc and macula were captured on a digital retinal camera following dilation of the pupils. Three uveitis-subspecialized ophthalmologists assessed each pigmented retinal lesion, and complete concordance of opinion was required to assign a toxoplasmic etiology. Serum T. gondii immunoglobulin (Ig)G levels were measured for those participants with retinal lesions judged to be toxoplasmic retinochoroiditis.

MAIN OUTCOME MEASURES

Prevalence of toxoplasmic retinochoroiditis.

RESULTS

Eight participants (0.16%) had retinal lesions that were considered to have the characteristic appearance of toxoplasmic retinochoroiditis, plus detectable serum T. gondii IgG, consistent with the diagnosis of toxoplasmic retinochoroiditis. On the assumption that 23.81% of retinal lesions occur at the posterior pole, as reported in a community-based survey conducted in Brazil (Sci Rep. 2021;11:3420), the prevalence of toxoplasmic retinochoroiditis was estimated at 0.67% or 1 per 149 persons.

CONCLUSIONS

Toxoplasmic retinochoroiditis is common in Australian adults. Efforts to quantify and address risk factors for human infection with T. gondii are justified.

Research on demographic, clinical and paraclinical aspects in pregnant women infected with Toxoplasma gondii

Toxoplasmosis is a zoonotic disease caused by the Toxoplasma gondii protozoan parasite. The aim of this study was to determine the frequency of acute toxoplasmosis or its presence in the medical history of 240 pregnant women, depending on age and geographical background. The second purpose was to analyze several medical aspects (clinical and paraclinical) in pregnant women with acute toxoplasmosis. The study identified several serological changes including positive toxoplasma IgM, IgG, and IgA antibodies. The chemiluminescence immunoassay (CLIA) method was used to detect T. gondii-specific IgM and IgG antibodies and the enzyme immunoassay (EIA) method to detect T. gondii-specific IgA antibodies. Of the 96 pregnant women (40%) infected with T. gondii, approximately 1/3 had acquired acute infection and 2/3 had a history of prior acute infection (P<0.0001). No statistically significant differences according to age groups (P=0.9384) were found in terms of serological profile. The number of patients with negative serology was significantly higher in urban areas than in rural areas (P<0.0001). The highest incidence among the pregnant women with acute toxoplasmosis with a single chain of ganglia affected was represented by those with the involvement of cervical lymph nodes (75%), the difference compared to the involvement of other chains of ganglia being statistically significant (P=0.0087). All 35 pregnant women with acute toxoplasmosis tested positive for T. gondii-specific IgM antibodies. Most pregnant women with acute T. gondii infection (57.1%) tested negative for T. gondii-specific IgM antibody serum titres within 3-6 months of presentation. The difference compared to other intervals from the moment pregnant women sought care was statistically significant (P=00002). Only 80% of all pregnant women with acute toxoplasmosis tested positive for T. gondii-specific IgA antibodies. Pregnant women with acute toxoplasmosis have a 3.3 times higher risk of pregnancy loss.