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Seroprevalence and clinical correlation in suspected cases of neurotoxoplasmosis
, Vidhya Thirumalaisamy1, Akshay Krishna1, Veena Haradara Bahubali1, Kavya Mallikarjun1, Arghadip Samaddar1, Valakunja Ganaraja2, Jitender Saini3, Manjunath Netravathi2, Siddaiah Nagarathna1,
*Corresponding author: Siddaiah Nagarathna, Department of Neuromicrobiology, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India. nagarathnachandrashekar@gmail.com
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Received: ,
Accepted: ,
How to cite this article: Lodha L, Thirumalaisamy M, Krishna A, Haradara Bahubali V, Mallikarjun K, Samaddar A, et al. Seroprevalence and clinical correlation in suspected cases of neurotoxoplasmosis. J Lab Physicians. 2025;17:347-55. doi: 10.25259/JLP_252_2025
Abstract
Objectives:
Toxoplasmosis is a zoonotic protozoan infection prevalent worldwide and has recently been associated with neuro-psychiatric conditions. The aim of this study was to retrospectively review suspected neurotoxoplasmosis cases tested at the center in the past 3 years (2020-2022) and describe the demography, clinical features, radiologic findings, risk factors, and prevalence of anti-toxoplasma antibodies in this patient population.
Materials and Methods:
A retrospective records review was carried out at a public-sector tertiary-level hospital and research center serving as a referral center for patients from all over India.
Statistical analysis:
Continuous variables were expressed in terms of median, interquartile range, maximum, and minimum; nominal variables were expressed in terms of frequencies and percentages. Chi-square test or Fisher’s test was used to establish associations between categorical variables. The Wilcoxon rank-sum test and the Welch two-sample t-test were used for continuous variables, as per the normality of the data.
Results:
A total of 225 sera from 281 patients were tested for anti-Toxoplasma antibodies, out of which 111 tested positive; therefore, the overall seroprevalence rate among suspected toxoplasmosis cases was 49.33%. The mean and median duration of illness were 84.82 days and 15 days, respectively. Altered sensorium, speech impairment, and limb weakness were significantly associated with the presence of anti-Toxoplasma antibodies in patient sera. Human Immunodeficiency Virus (HIV)-positive status and low CD4 T-cell count were also significantly associated with seropositivity.
Conclusions:
This study presents a comprehensive analysis of suspected neurotoxoplasmosis cases, identifies diagnostic clues, and highlights the challenges prevalent in the diagnosis of neurotoxoplasmosis.
Keywords
Laboratory diagnosis of toxoplasmosis
Neurological infections
Toxoplasmosis
INTRODUCTION
Toxoplasmosis is a zoonosis caused by the protozoan parasite Toxoplasma gondii, transmitted to humans through ingestion of viable tissue cysts in meat, by ingestion of oocysts in food or water, or through the transplacental route, or through organ transplantation. While it is usually an asymptomatic or self-limiting infection in humans, it may be life-threatening for fetuses, immunocompromised persons, and occasionally even immunocompetent persons.[1] This protozoan is omniscient in the environment and adapted to survive in a large number of animal hosts. It is estimated that one-third of the global human population is infected with T. gondii.[2] From its early recognition as a severe congenital infection to the current scenario of its association with various neuro-psychiatric conditions (such as schizophrenia, Alzheimer’s disease, bipolar disorder, epilepsy, and obsessive-compulsive disorder), research on this infection has come a long way.[3] However, effective control of human toxoplasmosis is yet to be achieved, in spite of several measures aimed at different stages of the transmission cycle.[4]
Although reliable estimates of the incidence of congenital toxoplasmosis are available, the incidence of acquired toxoplasmosis is less well elucidated, and the number of reported cases in different countries varies from 2.6 to 58/100,000.[4] In a study from North India published in 2020, an overall seropositivity of 21% was detected.[5] Another study from 2021 reported an overall Toxoplasma seropositivity of 36.88%.[6] Acquired toxoplasmosis in immunocompetent individuals is symptomatic in only 10-20% of cases and usually presents as a self-limited flu-like syndrome and lymphadenopathy, rarely progressing to ocular infection. Immunocompromised patients, however, present with systemic disease or involvement of the nervous system, lungs, or eyes, and the infection may take a fulminant course.[7] In human immunodeficiency virus (HIV)-infected patients, toxoplasmosis is the most common opportunistic infection of the central nervous system (CNS).[8] Diagnosis of human toxoplasmosis relies on direct detection of the pathogen from clinical specimens (using nucleic acid amplification techniques or histopathological staining) or by detection of specific antibodies in serum.[8]
The present study was carried out in a tertiary-level neurosciences center in the South Indian state of Karnataka, where the sero-diagnosis of toxoplasmosis is performed using NovaLisa enzyme-linked immunosorbent assay (ELISA) for combined detection of anti-toxoplasma immunoglobulin G (IgG) from serum and cerebrospinal fluid (CSF). The sensitivity and specificity of this kit for detecting IgG antibodies in serum are 98.25% and 98.45%, respectively, while the analytical sensitivity is 1.04 IU/mL. The study site is a referral center for neurological and neurosurgical cases from all over the state, as well as other states in the region. The aim of this study was to retrospectively review the suspected neuro-toxoplasmosis cases tested at the center in the past 3 years (2020-2022) and describe the demography, clinical features, radiologic findings, risk factors, and prevalence of anti-toxoplasma antibodies in this patient population. This study was carried out with the intent of detailing the characteristics of neuro-toxoplasmosis in this region and providing a baseline demographic and clinical analysis of this infection, which may guide the development and implementation of diagnostic services, preventive measures, and public health policies for neuro-toxoplasmosis.
MATERIALS AND METHODS
Study design and participants
A retrospective study of physical and electronic records of the neuromicrobiology laboratory and hospital was conducted at a public-sector tertiary-level hospital and research center serving as a referral center for patients from all over India.
All samples for T. gondii serology received between January 01, 2020, and December 31, 2022, were included. In our setting, T. gondii serology was requisitioned in cases with suspected neurotoxoplasmosis, defined as a compatible clinical syndrome [Supplementary data], presence of one or more mass lesions on brain imaging, and no other alternative diagnosis. T. gondii serology is also performed to rule out T. gondii infection or exposure in patients with atypical neurologic presentations and difficult diagnosis. Suspected neurotoxoplasmosis patients positive for anti-Toxoplasma IgG are classified as “probable neurotoxoplasmosis,” since laboratory confirmation can only be obtained using detection of protozoan nucleic acid in CSF or direct demonstration of parasite by examination of brain tissue.[9]
Data collection
The records of all patients tested for T. gondii serology from January 01, 2020, to December 31, 2022, were accessed from the laboratory information system. The results of anti-Toxoplasma antibody testing were analyzed for all patients to assess seropositivity. For further study, only patients whose medical records were available were included, and these records were accessed from the Medical Records Department. For these patients, all relevant data, such as demographic, clinical, radiological, and treatment details, along with the laboratory test results, were extracted and compiled in a Microsoft Excel spreadsheet.
Ethical clearance
As this study was a retrospective review of laboratory and hospital records, ethical clearance was not required. Patient confidentiality was maintained throughout the data collection process, and the patient data included in the study were anonymized.
Statistical analysis
The data obtained from the medical records were manually entered in Microsoft Excel (version Office 365). The data were appropriately recoded for the variables. The final sheet was imported into R version 4.2.3 using the “readxl” package, and further analysis was done using packages such as “tidyverse,” “gtsummary,” “flextable,” and their dependencies.
Continuous variables such as age and income were expressed in terms of median, interquartile range, maximum, and minimum. The outcome variables, which were nominal, were expressed in terms of frequencies and percentages. Further, the Chi-square test or Fisher’s test was used to find an association between categorical variables, and the Wilcoxon rank-sum test and the Welch two-sample t-test were used for the continuous variables, as per the normality of the data.
RESULTS
Overall results of anti-Toxoplasma antibody testing in serum and CSF of suspected cases
A total of 281 patients with suspected toxoplasmosis were tested at the laboratory over 3 years (January 2020 to December 2022).
Of these 281 patients, paired samples in the form of serum and CSF were obtained from 91 (32.38%) cases, while single samples in the form of only serum or only CSF were obtained from 134 (47.69%) and 56 (19.93%) patients, respectively.
A total of 225 serum samples from 281 patients were tested for anti-Toxoplasma antibodies, of which 111 tested positive; therefore, the overall seroprevalence rate among suspected toxoplasmosis cases was 49.33%, and these cases were classified as probable neurotoxoplasmosis.
Demographic distribution of suspected toxoplasmosis patients
Complete or partial medical records were available for 231 out of 281 patients, and further analysis was performed for these patients. The age and gender distribution of these patients have been summarized in Table 1. The majority, i.e., 195 (84.42%) of patients included in the study belonged to Karnataka state, while the remaining hailed from different states such as Andhra Pradesh (14, 6.06%), West Bengal (7, 3.03%), Tamil Nadu (5, 2.16%), Bihar (4, 1.73%), Orissa (2, 0.87%), Sikkim (1, 0.43%), Assam (1, 0.43%), Chhattisgarh (1, 0.43%), and Delhi (1, 0.43%).
| Number (percentage) | Range of age (years) | Median age (years) | Mean age (years) | SD of age (years) | |
|---|---|---|---|---|---|
| Males | 151 (65.37) | 6-68 | 39 | 38.79 | 12.58 |
| Females | 80 (34.63) | 4-71 | 40.5 | 40.01 | 13.22 |
| All cases | 231 (100) | 4-71 | 40 | 39.21 | 12.79 |
SD: Standard deviation
Clinical manifestations and laboratory results of suspected toxoplasmosis patients
Duration of illness was available for 218 suspected toxoplasmosis cases, and for these cases, the mean and median duration of illness were 84.82 days and 15 days, respectively. The most commonly seen clinical symptoms were headache (111, 47.84%), fever (90, 38.79%), and altered sensorium (84, 36.21%). All the clinical features seen in these patients have been listed in Table 2 along with their prevalence.
| Clinical manifestation | Number of cases (percentage); total n=231 |
|---|---|
| Headache | 111 (48.05) |
| Fever | 90 (38.96) |
| Altered sensorium | 84 (36.36) |
| Limb weakness | 71 (30.74) |
| Seizures | 70 (30.30) |
| Vomiting | 62 (26.84) |
| Speech disturbance | 39 (16.88) |
| Visual disturbance | 32 (13.85) |
| Nerve palsy | 25 (10.82) |
| Behavioral disturbance | 21 (9.09) |
| Gait abnormalities | 19 (8.23) |
| Memory disturbance | 17 (7.36) |
| Neck rigidity | 17 (7.36) |
| Dizziness or giddiness | 14 (6.06) |
| Lymphadenopathy | 11 (4.76) |
| Fatigue | 10 (4.33) |
| Bladder and/or bowel disturbances | 10 (4.33) |
| Confusion | 8 (3.46) |
| Myalgia | 5 (2.16) |
| Visual field loss | 5 (2.16) |
| Hydrocephalus | 4 (1.73) |
| Choreiform movements or athetosis | 1 (0.43) |
Among the 231 cases, 38 (16.45%) were HIV-negative, 154 (66.67%) were HIV-positive, and HIV status was unknown for 39 (16.88%) patients. Among the 154 HIV-positive patients, CD4+ T-cell count was available for 73 patients, and the mean and median CD4+ T-cell count were 166 cells/mm3 and 76 cells/mm3, respectively. Forty-two out of 70 (60%) patients had a CD4+ T-cell count of <100 cells/mm3. Furthermore, among the 154 HIV-positive patients, 55 (35.71%) were newly diagnosed with HIV during the current hospital visit, while 60 (25.97%) were old cases compliant with the prescribed anti-retroviral therapy (ART), and 39 (16.88%) old cases were not compliant with the treatment. The clinical and laboratory manifestations of HIV-positive cases have been summarized in Figure 1.
- (a) Clinical and (b) laboratory features of HIV-positive suspected neurotoxoplasmosis cases. HIV: Human immunodeficiency virus; CSF: Cerebrospinal fluid; cumm, cubic mililiter, CD4: Cluster of differentiation 4.
CSF was obtained by lumbar puncture in 191 cases and subjected to cytological and biochemical investigations. Pleocytosis, that is, a cell count of more than 5 cells/mm3, was seen in 117 cases. The pleocytosis was lymphocyte-predominant in 96 of 117 cases, neutrophil-predominant in 19 cases, and in the remaining two cases, there was no cellular type predominant. CSF glucose was lowered (i.e., <70 mg/dL) in 154 cases, while 141 cases had raised CSF protein (i.e., higher than 45 mg/dL).
A total of 197 serum samples and 117 CSF samples were received from 231 patients over 3 years. For 83 cases, paired samples, i.e., both serum and CSF were received, only serum sample was received from 114 cases, and only CSF was received from 34 cases. The results of anti-Toxoplasma antibodies from these samples have been summarized in Figure 2.
- Summary of results for 231 suspected cases whose medical records were available. CSF: Cerebrospinal fluid.
Radiological features of suspected cases
Out of 197 cases tested for serum anti-Toxoplasma IgG antibodies, a high index of radiological suspicion was noted in 69 cases [Table 3]. Among these cases, 66 cases showed the presence of one or more typical “ring-enhancing lesions” on magnetic resonance imaging, while in the remaining three cases, the radiology was atypical, but toxoplasmosis was considered as an important differential diagnosis. Common areas of CNS structure involvement were the parietal lobe in 25 cases, followed by the frontal lobe, basal ganglia, and thalamus in 23 cases each. Temporal and occipital lobes were involved in 18 and 17 cases, respectively. Grey-white junction involvement was also noted in 15 cases. Infratentorial structures, such as the brainstem and cerebellum, were involved in 20 and 16 cases, respectively. In 11 cases, all the above structures were involved in a diffuse manner. Overall, about 27 cases had additional associated meningeal enhancement [Figures 3 and 4]. Among the other remaining 128 of 197 cases, radiological records were not available for 13 patients (eight were IgG positive), normal studies were obtained in three cases (one was IgG-positive), and in 112 cases, features that were non-specific or suggestive of other etiologies were noted (45 were IgG-positive).
| Feature | n | IgG Negative, n=102 (51.78%)1 | IgG Positive, n=95 (48.22%)1 | Total, n=1971 | Test statistic | P-value |
|---|---|---|---|---|---|---|
| Altered sensorium | 197 | 29 (28%) | 44 (46%) | 73 (37%) | 6.7 | 0.0092 |
| Speech impairment | 197 | 10 (9.8%) | 23 (24%) | 33 (17%) | 7.3 | 0.0072 |
| Limb weakness | 197 | 24 (24%) | 40 (42%) | 64 (32%) | 7.7 | 0.0052 |
| Radiology suggestive of toxoplasmosis | 197 | 27 (26%) | 42 (44%) | 69 (35%) | 6.8 | 0.0092 |
| HIV status | ||||||
| Negative | 161 | 23 (30%) | 12 (14%) | 35 (22%) | 6.1 | 0.0132 |
| Positive | 53 (70%) | 73 (86%) | 126 (78%) | |||
| CD4+cell count | ||||||
| Median (IQR) (cells/cumm) | 62 | 164 (64, 302) | 46 (28, 108) | 66 (35, 168) | 684 | 0.0023 |
| Range | 13, 1,350 | 8, 668 | 8, 1,350 | |||
| CD4+cell count | ||||||
| <100 cells/cumm | 62 | 15 (60%) | 11 (30%) | 26 (42%) | 5.6 | 0.0182 |
| ≥100 cells/cumm | 10 (40%) | 26 (70%) | 36 (58%) | |||
| CSF cell count (per cumm) | ||||||
| Median (IQR) | 159 | 13 (3, 62) | 7 (1, 27) | 9 (2, 44) | 3,790 | 0.0234 |
| Range | 0, 1600 | 0, 320 | 0, 1600 | |||
| CSF Lymphocytes (per cumm) | ||||||
| Median (IQR) | 157 | 10 (2, 49) | 5 (1, 17) | 7 (1, 27) | 3,722 | 0.0184 |
| Range | 0, 1440 | 0, 171 | 0, 1440 |
1P-value was calculated by n (%), 2Pearson’s Chi-squared test; 3Welch two-sample t-test; 4Wilcoxon rank sum test. IgG: Immunoglobulin G, HIV: Human immunodeficiency virus, CSF: Cerebrospinal fluid, IQR: interquartile range; P-value of <0.05 is considered statistically significant
- Brain MRI T1 axial image showing (a) hypointense lesion in left thalamus (white arrow), (b,c) which is hyperintense on T2 and FLAIR sequences (white arrow), (d) with areas of blooming within in SWI sequence (white arrow), (e,f) with areas of diffusion restriction in DWI and ADC sequences (white arrow), (g) showing enhancement in T1 post contrast sequence (white arrow). (h) Similar ring enhancing lesion noted in subcortical white matter suggestive of CNS toxoplasmosis (white arrow). ADC: Apparent Diffusion Coefficient, DWI: Diffusion-weighted imaging, FLAIR: Fluid-Attenuated Inversion Recovery, SWI: Susceptibility Weighted Imaging.
- Brain MRI FLAIR axial images showing different areas of “toxoplasma” lesions - involving (a) right thalamus (white arrow), (b) brainstem, occipital and temporal lobe (white arrow), (c) occipitotemporal region (white arrow), (d) diffuse involvement of brain structures (white arrow), (e) right frontal lobe (white arrow), (f) right parietal lobe (white arrow), (g) cerebellum and brainstem (white arrow), and (h) thalamus with mass effect (white arrow).
Association of demographic, clinical, and laboratory features with seropositivity
A total of 197 patients’ serum specimens were tested for anti-Toxoplasma IgG antibodies, and 95 of them tested positive, yielding an overall seroprevalence of 48.22%. The seroprevalence among HIV-negative cases (n = 35) was 34.29%, while among HIV-positive cases (n =126), it was 57.94%. Association of various factors, including demographic, clinical, and laboratory findings, with seropositivity was evaluated using the Chi-square test (for categorical variables) and univariable logistic regression (for nominal variables). The factors found to be significantly associated with seropositivity have been summarized in Table 3, and the results for all factors are available in the Supplementary Data. Reference range for CSF protein in the testing laboratory was 15-40 mg/dL, and for CSF glucose was 50-80 mg/dL.
From the 231 cases included for analysis, 117 CSF specimens were received, of which 70 (59.83%) tested positive for anti-Toxoplasma IgG antibodies. Among these 70 cases, paired serum specimens were positive for anti-Toxoplasma IgG antibodies in 47 (67.14%) cases, and in the remaining cases, serum was either negative (3, 4.29%) or not tested (20, 28.57%).
Out of the 231 patients whose records were studied, specific treatment for toxoplasmosis, i.e., sulfadiazine and pyrimethamine, was initiated for only 56 (24.24%) patients, while 147 (63.64%) patients received other treatment. For 28 (12.12%) patients, treatment records were not available. The majority of the patients were discharged (116, 50.22%) or referred (62, 26.84%) to other centers for continuation of care. Fourteen (6.06%) patients left the hospital against medical advice, while one patient (0.43%) died, and the outcomes of 38 (16.45%) patients were not available on their records.
DISCUSSION
The dire consequences of toxoplasmosis as a congenital infection and as an opportunistic infection in immunocompromised patients are well described in the literature; however, it may also cause severe infections in immunocompetent hosts.[10] Various studies conducted in India have reported variable Toxoplasma IgG seroprevalence rates, ranging from 1.38% to 34.84%.[5,6,11,12] Higher seroprevalence is reported from Southern India compared to the northern parts.[11] The pooled seroprevalence of toxoplasmosis in HIV patients worldwide was reported to be 35.8%, with the highest prevalence in North Africa and the Middle East (60.7%), followed by Latin America and the Caribbean (49.1%), sub-Saharan Africa (44.9%), and the Asia-Pacific regions (25.1%).[13] In the present study, a higher seroprevalence (i.e., 49.33%) has been reported, which is likely due to the center being a national-level referral center.
The reported manifestations of neurological toxoplasmosis include encephalitis, meningitis, focal neurologic deficits, cranial nerve palsies, Guillain-Barré syndrome, and spinal lesions.[10] Commonly seen signs and symptoms include fever, headache, mental confusion, seizures, ataxia, behavioral or psychological abnormalities, and visual abnormalities.[9] The findings of the present study are in line with these reports, with headache, fever, altered sensorium, and seizures being the most common presenting symptoms in suspected toxoplasmosis cases. Moreover, it was found in this study that altered sensorium, speech abnormalities, and limb paresis/paralysis were significantly associated with the presence of anti-Toxoplasma antibodies in serum.
The typical radiological features of neurotoxoplasmosis include a typical “eccentric target sign” on magnetic resonance imaging, commonly seen in the basal ganglia or frontal and parietal lobes.[9] In the present study, suggestive radiological findings were observed in 69 (35.03%) of cases studied for seroprevalence, and it was significantly associated with seropositivity. However, seropositivity was seen even among the cases without these typical radiological features, indicating the high variability in radiological manifestations of neurotoxoplasmosis.
Patients with HIV infection are at increased risk of toxoplasmosis, especially if the CD4+ T-cell count falls below 100 cells/cumm, with Toxoplasma encephalitis being the most important clinical presentation.[14] In the present study, HIV infection was statistically significantly associated with seropositivity; thus, it reinforces the importance of HIV infection as a risk factor for neurotoxoplasmosis. Furthermore, the CD4+ T-cell count was found to be significantly associated with Toxoplasma seropositivity, and seropositivity was significantly higher in patients with a CD4+ T-cell count of <100 cells/cumm, compared to patients with a higher CD4+ T-cell count.
CSF pleocytosis, and more specifically, CSF lymphocytic pleocytosis, were significantly associated with seropositivity. These findings are also well documented in the previous studies.[10] Median CSF protein was raised in both seropositive and seronegative groups, but it was not significantly associated with anti-Toxoplasma seropositivity. Since the study was conducted in a neurology reference center, abnormal CSF findings such as raised protein are likely to be observed in most cases presenting to this hospital. On the other hand, median CSF glucose was normal in both groups. Thus, CSF protein and glucose are non-specific markers and of lesser importance in ruling out a differential diagnosis.
In addition to serum, antibody detection was also performed with CSF specimens, and a positivity rate of 67.14% was obtained from 117 specimens tested. Published data supporting the use of CSF antibodies as a diagnostic test of neuro-toxoplasmosis are scarce, as only limited reports describing its utility have been published. One study of 22 autopsy cases confirmed cerebral toxoplasmosis reported 100% sensitivity and specificity of T. gondii IgG from CSF.[15] Another study of CSF specimens from 25 autopsy-proven cases of neuro-toxoplasmosis reported detection of IgG antibodies by ELISA in 92% of the cases.[16] However, a larger study consisting of 55 HIV-infected patients with presumptive diagnosis of neurotoxoplasmosis found that the index of intrathecal antibody production had low sensitivity (42.8%) and specificity (70.8%).[17]
In the present study, out of the 70 cases where CSF IgG was positive, 37 patients had strong clinical and/or radiological evidence of neurotoxoplasmosis. In the remaining patients, the interpretation of CSF IgG is challenging, especially in immunocompromised patients, due to the increased permeability of the brain barrier, allowing increased transfer of serum antibodies into CSF. Even in immunocompetent patients, a single serum positive for anti-Toxoplasma IgG in an immunocompetent patient has to be repeated after 3 weeks, an additional test for IgM antibodies, and determination of the duration of the infection by avidity testing is also indicated.[18]
Limitations
The majority of non-congenital or horizontal spread of toxoplasmosis in humans occurs by ingestion of contaminated meat (containing tissue cysts), or by ingestion of contaminated soil, water, or food (containing sporulated cysts), or by exposure to feline feces.[14] However, these typical risk factors may be absent in more than half of the patients with severe toxoplasmosis.[10] No such risk factors were elicited from patients included in the present study, which is one of the limitations of the study.
Another limitation of the study is the lack of follow-up data after treatment and discharge from the study center. Long-term follow-up records were not available for these patients since the study center is a dedicated neurology hospital, and most patients are discharged and referred to other hospitals as they require multispecialty care. The extremely low mortality rate observed in this study is not representative of the true mortality rate of neurotoxoplasmosis, which is reported to range from 8% to 30%.[9,10]
Finally, the study is limited by the lack of a confirmatory test for toxoplasmosis, i.e., detection of parasite nucleic acid in CSF. This test was not performed in the laboratory due to the unavailability of standardized and validated positive controls. Therefore, the study is focused on suspected neurotoxoplasmosis cases.
CONCLUSIONS
A comprehensive analysis of suspected neurotoxoplasmosis cases has been presented in this study, and several factors to help establish an etiological diagnosis have been identified. Diagnosis of neurotoxoplasmosis remains challenging, especially in immunocompetent cases. Even though serology is the routine method of diagnosis, interpretation is not straightforward. A single serum sample positive for anti-Toxoplasma IgG in an immunocompromised patient may represent a latent infection and warrants treatment as per the clinical presentation and degree of immunosuppression. Thus, serology must be combined with radiology and molecular diagnostic methods to facilitate early diagnosis and initiation of therapy.
Author’s contributions:
NS: Conceptualization; NS, LL, VT, AK: Methodology; LL, VT, AK, KM: Formal analysis and investigation; LL, VT: Writing original manuscript; NS, VKHB, AS, GVH, JS, NM: Writing – review and editing; LL, VT, AK, KM: Validation; NS, VKHB, AS, NM: Project administration; NS, VKHB, AS, NM, GVH, JS: Resources; NS: Supervision and guarantor.
Ethical approval:
The Institutional Review Board approval is not required as this is a retrospective review of laboratory and hospital records.
Declaration of patient consent:
Patient’s consent not required as patients identity is not disclosed or compromised.
Conflicts of interest:
There are no conflicts of interest.
Use of artificial intelligence (AI)-assisted technology for manuscript preparation:
The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript, and no images were manipulated using AI.
Financial support and sponsorship: Nil.
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