Neuro-ophthalmic features in pediatric tubercular meningoencephalitis

The rare manifestations in tuberculous meningoencephalitis: a review of available literature

Aim: Tuberculous meningitis is an infectious disease of the central nervous system caused by Mycobacterium tuberculosis (M. tuberculosis). It mainly involves the meninges and brain parenchyma, as well as the spinal cord and meninges; Disability and mortality rates are high. In recent years, due to the increase of drug-resistant tuberculosis patients, population mobility and the prevalence of acquired immune deficiency syndrome, the incidence rate of tuberculosis has increased significantly, and tuberculous meningitis has also increased.Methods: At present, tuberculosis is still a worldwide infectious disease that seriously threatens human health, especially in underdeveloped and developing countries. China is the largest developing country in the world with a large population.Results: The situation of tuberculosis prevention and control is grim. Its disability rate is the highest in tuberculosis infection. In addition to the common non-specific manifestations, tuberculous meningoencephalitis may also have rare manifestations of stroke, hearing loss and visual loss.Conclusion: Understanding and timely improvement of corresponding examinations and targeted treatment will help improve the prognosis of patients.

Neuro-ophthalmic manifestations of tuberculosis

Neuro-ophthalmic features are a known association in tuberculosis, especially common in central nervous system tuberculosis (CNS-TB). They are mostly the result of the visual pathway and/or ocular motor and other cranial nerve involvement. Furthermore, toxic optic neuropathy and paradoxical response to anti-tubercular drugs (ATT) are also not uncommon. The etiopathogenesis is by the complex interplay of various factors like exudates, vasculitis, arachnoiditis, presence of tuberculomas, hydrocephalus, brain infarcts and/or immune-mediated reaction. The entity often poses a diagnostic dilemma for the ophthalmologists/neuro-ophthalmologists and may lead to irreversible vision loss. The presence of neuro-ophthalmic features not only affect the visual outcome but are also predictors of systemic morbidity of the disease. Therefore, understanding and knowledge about this entity are necessary for the comprehensive management of the disease. While various forms of TB including CNS-TB have been well-dealt with in literature, little is discussed specifically about the neuro-ophthalmic manifestations of tuberculosis. Therefore, the purpose of this review is to highlight current understanding of the types of neuro-ophthalmic involvement in tuberculosis, its etiopathogenesis, diagnosis and management.

Ophthalmological manifestation in patients of tuberculous meningitis

BACKGROUND

Vision impairment, blindness in particular is a devastating complication in patients with tuberculous meningitis. However, information regarding ophthalmological manifestation and its impact on vision is sparse in the literature. This study evaluated the spectrum of ophthalmological manifestations in tuberculous meningitis, including retinal nerve fiber layer thickness assessment by optic coherence tomography and its correlation with visual and clinical outcome.

METHODS

This was a prospective observational study done from October 2015 to March 2017. Consecutive patients of tuberculous meningitis, diagnosed as per consensus case definition were included in the study. The patients were divided into two categories: uncomplicated and complicated tuberculous meningitis. Clinical evaluation, cerebrospinal fluid examination and contrast enhanced MRI of brain was done. Detailed ophthalmological evaluation including optic coherence tomography was done in all patients. All the patients were followed for 6 months. The primary outcome was blindness or low vision after 6 months. The secondary outcome was death or severe disability after 6 months. It was defined as modified Barthel index (MBI) ≤ 12 at 6 months (including disability plus death). Appropriate statistical analysis was done.

RESULTS

Out of 101 patients of tuberculous meningitis, 47 patients of TBM belonged to uncomplicated category, while 54 patients were of complicated group. The visual impairment was present in 24 out of 101 (23.76%) patients out of which 20 (19.8%) patients had low vision while 4 (3.96%) had blindness. The visual impairment was more evident in complicated group, low vision 0.03 (1.2-31.5). The most common abnormality on fundus examination was papilledema (22.8%). The complicated group had more incidence <0.0001 (19.6-48). Optic atrophy was found in three patients while choroid tubercles were found in eight patients (all complicated TBM group). RNFL thinning was noted in 10 patients in both the eyes. On univariate analysis, presence of diplopia at baseline, impairment of color vision at baseline, visual impairment at baseline, cranial nerve VIth involvement, optic atrophy and papilledema at baseline, RNFL thinning, abnormal VEP and baseline MBI were associated with poor visual outcome. On multivariate analysis, none of the factors were found to be independently associated with poor visual outcome. On univariate analysis, many factors including baseline MRC staging, altered sensorium, seizure, hemiparesis, basal exudates, infarcts, optochiasmaticarachnoiditis, visual impairment at baseline were found to be associated with poor clinical outcome at 6 months. On multivariate analysis, presence of seizure (P = 0.047, odds ratio = 78.59, 95% confidence interval (1.07-578.72)) was the only factor found to be independently associated with poor outcome.

CONCLUSION

Wide spectrum of ophthalmological manifestation was observed in patients of tuberculous meningitis. The visual impairment was more evident in complicated tuberculous meningitis. Ophthalmological findings like optic atrophy, papilledema and RNFL thinning were associated with poor visual outcome on univariate but not multivariate analysis. Visual impairment at baseline, among other factors was associated with poor clinical outcome on univariate analysis, whereas seizure was the only factor independently associated with poor outcome on multivariate analysis.

Tuberculous Meningitis in Children and Adults: New Insights for an Ancient Foe

PURPOSE OF REVIEW

Tuberculous meningitis is the most devastating manifestation of infection with Mycobacterium tuberculosis and represents a medical emergency. Approximately one half of tuberculous meningitis patients die or suffer severe neurologic disability. The goal of this review will be to review the pathogenic, clinical, and radiologic features of tuberculous meningitis and to highlight recent advancements in translational and clinical science.

RECENT FINDINGS

Pharmacologic therapy includes combination anti-tuberculosis drug regimens and adjunctive corticosteroids. It is becoming clear that a successful treatment outcome depends on an immune response that is neither too weak nor overly robust, and genetic determinants of this immune response may identify which patients will benefit from adjunctive corticosteroids. Recent clinical trials of intensified anti-tuberculosis treatment regimens conducted in Indonesia and Vietnam, motivated by the pharmacologic challenges of treating M. tuberculosis infections of the central nervous system, have yielded conflicting results regarding the survival benefit of intensified treatment regimens. More consistent findings have been observed regarding the relationship between initial anti-tuberculosis drug resistance and mortality among tuberculous meningitis patients. Prompt initiation of anti-tuberculosis treatment for all suspected cases remains a key aspect of management. Priorities for research include the improvement of diagnostic testing strategies and the optimization of host-directed and anti-tuberculosis therapies.

Vision loss in tuberculous meningitis

Vision loss is a disabling complication of tuberculous meningitis. Approximately, 15% of survivors are either completely or partially blind. All structures of the visual pathway may be affected in tuberculous meningitis. Optic nerve and optic chiasma are most frequently and dominantly affected. Thick-gelatinous exudates lying over the base of brain, are the pathological hallmark of tuberculous meningitis and are responsible for almost all of its major complications, including vision loss. Strangulation of optic nerves and optic chiasma by the exudates, compression over optic chiasma by the dilated third ventricle, raised intracranial pressure, endarteritis, shunt failure, bacterial invasion of optic nerves and drug-induced optic nerve damage are important reasons that are considered responsible for vision loss. Prompt antituberculosis treatment is the best management option available. Immunomodulatory drugs and cerebrospinal fluid diversion procedures are of limited help. Early recognition and treatment of tuberculous meningitis is the only way forward to tackle this problem.

Isolated Fourth Nerve Palsy in Tuberculous Meningitis

Tuberculous meningitis is a type of subacute meningitis and like other intracranial processes can compromise ocular motor nerves, causing palsies. Trochlear nerve is an unusual isolated manifestation in this type of pathology. The authors report a 5-year-old boy presented in their clinic with a trochlear nerve palsy as unique neurological manifestation of tuberculous meningitis. Treatment with complete anti-tuberculous therapy and botulinum A toxin was needed to get the complete resolution of the nerve palsy. In tuberculous meningitis, the presence of high protein levels and higher number of cells in cerebrospinal fluid is associated with cranial nerve involvement. Usually cranial nerve palsies occur in combination. VI cranial nerve alone or a combined disorder of VI and III cranial nerves are the palsies most frequently presented. Much less common is an isolated disorder of IV cranial nerve in the course of meningitis. The length of full treatment with anti-tuberculous therapy in this case was of 1 year. The persistence of palsy 1 month after the beginning of the symptoms indicated the possibility of a botulinum toxin injection with complete resolution of the process without disability, ocular motility has remained normal on follow-up.

An unusual cause of visual impairment in tuberculous meningitis

Impairment of vision is a devastating complication of tuberculous meningitis which may occur as a result of increased intracranial pressure, compression over the visual pathways or vasculitis. We herein present occurrence of neuroretinitis in a 35-year-old lady presenting with low grade fever and headache for one month, and associated with diminution of vision from 3 weeks. She was diagnosed as a case of definite tuberculous meningitis and initiated on anti-tuberculous treatment as per WHO guidelines with supplemental corticosteroids. Marked improvement in vision was observed and at 3 months of follow-up the patient was asymptomatic. Direct ophthalmoscopy, visual field analysis, fluorescein angiography, optical coherence tomography and magnetic resonance imaging of the brain were done to document the ophthalmological findings. Neuroretinitis, being an unusual cause of visual impairment in tuberculous meningitis, must be considered in patients without any evidence of raised intracranial pressure or compression, and with normal fluorescein angiography. We suggest that neuroretinitis may be added to list of causes of visual impairment in patients with tuberculous meningitis.

Tuberculous meningitis

Tuberculous meningitis is a severe form of extrapulmonary tuberculosis. The exact incidence and prevalence are not known. In countries with high burden of pulmonary tuberculosis, the incidence is expected to be proportionately high. Children are much more vulnerable. Human immunodeficiency virus-infected patients have a high incidence of tuberculous meningitis. The hallmark pathological processes are meningeal inflammation, basal exudates, vasculitis and hydrocephalus. Headache, vomiting, meningeal signs, focal deficits, vision loss, cranial nerve palsies and raised intracranial pressure are dominant clinical features. Diagnosis is based on the characteristic clinical picture, neuroimaging abnormalities and cerebrospinal fluid changes (increased protein, low glucose and mononuclear cell pleocytosis). Cerebrospinal fluid smear examination, mycobacterial culture or polymerase chain reaction is mandatory for bacteriological confirmation. The mortality and morbidity of tuberculous meningitis are exceptionally high. Prompt diagnosis and early treatment are crucial. Decision to start antituberculous treatment is often empirical. WHO guidelines recommend a 6 months course of antituberculous treatment; however, other guidelines recommend a prolonged treatment extended to 9 or 12 months. Corticosteroids reduce the number of deaths. Resistance to antituberculous drugs is associated with a high mortality. Patients with hydrocephalus may need ventriculo-peritoneal shunting. Bacillus Calmette-Guérin vaccination protects to some degree against tuberculous meningitis in children.

Acquired abducens nerve palsy secondary to tuberculosis

BACKGROUND

Tuberculosis is a serious, and unfortunately common, infectious disease caused by the organism Mycobacterium tuberculosis. The incidence, mortality, and physical/ophthalmologic effects are well documented. Although most common ophthalmologic findings include optic neuropathy and uveitis, cranial nerve palsies may also present secondary to intracranial inflammation.

CASE REPORT

A 17-year-old Somalian girl was referred to the eye clinic with the chief concern of intermittent diplopia and headaches. Although monocular visual acuity was excellent, ocular positioning tests confirmed a subtle abduction deficit of the right eye. Medical history was remarkable for active tuberculosis.

CONCLUSION

Tuberculosis is a mediating factor for abducens nerve palsy in children. Understanding the relationship between the disease process and ocular ramifications is imperative for competent management.

Choroidal Tubercles in Neurotuberculosis: Prevalence and Significance

PURPOSE

Neurotuberculosis is a relatively common form of tuberculosis and may be seen in 1-10% of patients of systemic tuberculosis and may present in several forms. Ocular lesions are frequently seen, most commonly optic nerve lesions. Limited data are available for choroidal tubercles. We conducted a prospective study 1) to determine the prevalence of choroidal tubercles in a cohort of patients of neurotuberculosis as well as its relative prevalence in the various morphological manifestations and 2) to study the role of co-existent systemic tuberculous infection.

METHODS

IRB-approved prospective cross-sectional observational study. A hospital-based cohort of patients underwent a detailed physical, laboratory and ocular evaluation.

RESULTS

A total of 52 (20 male, 32 female) patients were evaluated with tubercles being seen in 23 eyes (18 patients, 34.6%). Twenty four patients (46.12%, 16 female, 8 male) presented with intracranial granulomas and 28 (53.8%, 16 female, 12 male) presented with tuberculous meningitis. Tubercles were seen in 10 eyes of 8 (28.5%) patients with tuberculous meningitis and in 13 eyes of 10 patients (41.6%) with intracranial granulomas. This result is not statistically significant. Twenty seven patients (51.9%) had neurotuberculosis without systemic infection, whereas 25 (48.1%) patients had systemic foci. Tubercles were seen in 18 eyes (13 patients) with systemic foci and in 5 eyes (5 patients) of neurotuberculosis alone. The odds ratio for the presence of systemic tuberculosis when choroidal tubercles are present is 5.6 (95% confidence interval: 1.39-24.49, statistically significant [p = 0.005]).

CONCLUSIONS

Tubercles were equally likely to occur in either manifestation of neurotuberculosis, and their presence was related to the presence of systemic focus of tuberculous infection. The presence of choroidal tubercles may serve as a diagnostic marker for the presence of an underlying systemic infection.

A case of oculomotor nerve palsy and choroidal tuberculous granuloma associated with tuberculous meningoencephalitis

We report a rare case of oculomotor nerve palsy and choroidal tuberculous granuloma associated with tuberculous meningoencephalitis. A 15-year-old male visited our hospital for an acute drop of the left eyelid and diplopia. He has been on anti-tuberculous drugs (isoniazid, rifampin) for 1 year for his tuberculous encephalitis. A neurological examination revealed a conscious clear patient with isolated left oculomotor nerve palsy, which manifested as ptosis, and a fundus examination revealed choroidal tuberculoma. Other anti-tuberculous drugs (pyrazinamide, ethambutol) and a steroid (dexamethasone) were added. After 3 months on this medication, ptosis of the left upper eyelid improved and the choroidal tuberculoma decreasedin size, but a right homonymous visual field defect remained. When a patient with tuberculous meningitis presents with abrupt onset oculomotor nerve palsy, rapid re-diagnosis should be undertaken and proper treatment initiated, because the prognosis is critically dependent on the timing of adequate treatment.

Oculo-renal disorders in infectious diseases

BACKGROUND

The aim of this article is to review the potential ocular and renal disorders in infectious diseases to which humans are susceptible and to determine prevalence of these diseases.

METHODS

Published cases of oculo-renal disorders associated with various infectious diseases were collected from the international literature by searching the MEDLINE database (PUBMED 1970-2004) for original reports and review articles published in English. Citations from papers retrieved were screened and retrieved papers were evaluated.

RESULTS

Based on the screened data, we propose a practical, structure-oriented checklist of such lesions divided into bacterial, viral, parasital, and fugal infections.

CONCLUSION

The oculorenal manifestations of infectious diseases may be flagrant or subtle. Awareness of the signs and symptoms of infections allows early recognition and prompt, appropriate management. The clinical presentation and relative frequency of those manifestations are reviewed.

The eye in neurological disease

Neurological disease can involve the eye in many ways. Every structure--the conjunctiva, cornea, anterior chamber, iris, lens, vitreous humour, retina, choroid, and optic nerve--can be affected. In many cases, ocular involvement is the first manifestation of the underlying disease. In such cases, the ability of the physician to recognise the nature and significance of the ocular abnormality can lead to early diagnosis and successful treatment of the underlying condition. In other cases, recognition of the ocular abnormality can prevent permanent visual dysfunction.