We report a newly diagnosed 34-year old HIV-infected male patient who presented with clinical semiology consistent with new-onset focal motor seizure with impaired awareness involving the right upper and lower limbs. Brain MRI showed symptomatic left frontal ring enhancing mass lesion and smaller lesion on left frontal region likely indicating CNS toxoplasmosis and EEG showed predominant left frontal focal slowing, further supporting the lesion on the left side was symptomatic. Considering his underlying HIV infection, he was started on cART, anti-toxoplasmosis medication, and anticonvulsant.
Toxoplasmic encephalitis (TE) is caused by the protozoan Toxoplasma gondii. Disease appears to occur almost exclusively because of reactivation of latent tissue cysts . In patient with advanced HIV infection, CD4 cells below 200 are much vulnerable to develop TE [1,3,7]. Our patient was a newly diagnosed patient with advanced immunosuppression likely predisposing him to develop CNS toxoplasmosis. A study reported by Yacouba et al. 2014  showed the overall prevalence of seizures among HIV-infected patient to be 45.2% and generalized seizure type to be the predominant type (75.8%) followed by partial seizure (15.2%) . Our patient had a symptomatic focal lesion in the left frontal lobe, which likely explains the semiology of focal motor seizure on the right hemibody. Likewise, the associated loss of consciousness reported in the present case could be explained by the higher tendency of frontal lobe seizures to rapidly generalized to the contralateral hemisphere resulting in reduced mentation .
Wide variety of disorders may result in intracranial space occupying lesions (ICSOL) in individuals with advanced HIV infection [6,8,10,11]. According to a review done by Pillay et al. 2018  out of 110 brain CT scan of admitted HIV infected patients, 80.9% includes a differential comprising toxoplasmosis or tuberculoma . This indicates TE is common among admitted HIV + patients presenting with ICSOL. In resource-limited settings, one of the major questions about seizures and seizure disorders during the process of caring for people with HIV is to identify the underlying cause of the seizure . Brain neuroimaging including MRI/ or CT scans and EEG are the two vital investigations helpful in identifying the underlying structural lesions which resulted in seizure disorder [6,12]. Our patient had both brain MRI and EEG which showed a possible culprit lesion causing the symptomatic focal seizure. Early diagnosis, identification of underlying brain pathology, timely management of HIV-associated seizure is critical, because untreated and missed HIV-associated seizure is always associated with increased risk of mortality and morbidity among HIV infected individuals [1,12].
Identifying seizure causes⸻ a major challenges in resource-limited settings
Identifying the cause of seizure is equally important to diagnosing seizure; because seizure recurrence is directly related to the presences or absences of underlying structural abnormality . Furthermore, patients with advanced HIV infections are more likely to have symptomatic seizure as a result of causes such as: cerebral toxoplasmosis, tuberculoma, cryptococcoma, HIV-associated malignancies etc [2,3,6,8,13]. In order to identify and classify seizure disorders, it’s important to have brain MRI/ or CT scan and EEG of the patients . However, resource-limited settings such as sub-Saharan African region is universally known for its major neurological services and care deficiency [14–16]. Likewise, a 2004 report by WHO showed the number of specialists in neurology in Africa, at 0.03 per 100,000 population, is lower than in the other who regions . To overcome such major challenge in resource limited settings, it’s advisable for care givers to depend on their clinical skills of Neurolocalization in order to determine if the patient had underlying structural abnormality. Our patient presented with new-onset right hemibody focal motor seizure associated with loss of consciousness. Therefore, we can clinically localize our patient’s symptoms to left hemispheric cortical region. Furthermore, the prominent motor features of our patient’s seizure semiology further help us to localize the lesion in frontal lobe .
Considering the high prevalence of HIV infection and associated seizure among people living with HIV in sub-Saharan Africa, this case fairly highlights on the importance of utilizing advanced imaging techniques such as MRI and EEG in identifying the underlying causes of HIV-associated seizures.