Sudden blindness due to bilateral optic neuropathy associated with cryptococcal meningitis in an AIDS patient

Infectious optic neuropathy (ION), how to recognise it and manage it

Optic neuropathy can be of infectious or non-infectious/idiopathic aetiology. Many infectious organisms can cause optic neuropathy that can be of varied presentation including papillitis, retrobulbar optic neuritis, neuroretinitis, and optic perineuritis. Detailed history, ocular, systemic/neurologic examination along with appropriate laboratory evaluation can help clinicians to identify the infectious agent causing optic neuropathy. In spite of recent advanced techniques in serological testing and molecular diagnostics like polymerase chain reaction (PCR), the identification of these pathogens is still a diagnostic challenge. It is ideal to have an infectious disease (ID) consultant in the management team, as most of these infections are multisystem involving diseases. Most infectious agents can be effectively treated with specific antibiotics, with or without corticosteroid therapy, but visual recovery is highly variable and depends entirely on early diagnosis of the causative agent. This review article will provide an overview of common pathogens involved in ION and will describe their management paradigms.

Clinical Characteristics of HIV-Associated Optic Neuritis

Introduction

Acute optic neuritis (ON) has been increasingly reported in patients infected with human immunodeficiency virus (HIV). We aimed to describe clinical characteristics of HIV-infected patients with ON.

Materials and Methods

This observational retrospective study was performed from January 2008 to January 2016 in a university hospital in Bangkok, Thailand. Demographic data and clinical manifestations were retrospectively reviewed.

Results

We included 10 HIV-infected patients and divided them into two groups: infectious and non-infectious ON. There were six patients in the infectious ON group (five males, mean age 33.6 years, median CD4 cell counts during ON episodes 36.5 cells/µL, high viral loads, median initial visual acuity [VA] 1.7, median VA difference [initial VA – follow-up VA] 0). Four patients developed cryptococcal meningitis and 2 developed neuro-syphilis. They were treated with amphotericin B plus fluconazole and penicillin G sodium, respectively. There were four patients in the non-infectious ON group (two males, mean age 44.3 years, median CD4 cell count during acute ON 157.5 cells/µL, undetectable viral loads, median initial VA 1.3, and median VA difference 1.2). They were given corticosteroid treatments. There were no statistically significant differences between the two groups with respect to age, sex, and initial VA. There were statistically significant differences in median VA difference and median CD4 cell counts between the two groups (p=0.02 and 0.03, respectively). There was a significant correlation between CD4 counts and duration in three non-infectious ON patients treated with antiretroviral therapy (ART, p<0.001).

Discussion

Patients with infectious ON had low initial CD4 counts and high viral loads. Patients with non-infectious ON had increasing CD4 cell counts and undetectable HIV viral load following ART. The findings are highly suggestive of immune reconstitution inflammatory syndrome. The CD4 cell counts and viral loads may help to identify the type of acute ON in HIV-infected patients and establish proper therapies.

Fishing in muddy waters- co-existing dual intracranial pathology in PRES: A case series and review of literature

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state often characterized by altered mental state and is seen in various clinical settings. Although it is often reversible, it may result in long term sequelae. The typical and atypical neuroimaging findings seen in PRES have been previously well-described in the literature. However, the presence of other co-existing intracranial lesions along with PRES can occasionally confound the imaging findings and poses a diagnostic challenge. Herein, the authors report four cases of PRES with etiologically different co-existing intracranial lesions confounding the clinical and imaging manifestations. When presented with atypical imaging findings in PRES, the possibility of a co-existing intracranial pathology with superimposed imaging findings should be considered.

Cryptococcosis in an Infectious Diseases Hospital of Buenos Aires, Argentina. Revision of 2041 cases: Diagnosis, clinical features and therapeutics

BACKGROUND

Cryptococcosis is still a life-threatening mycosis that continues to be of serious concern in Latin American countries, especially among HIV+positive population. However, there is not any reliable information about the prevalence of this disease in this region.

AIMS

The aim of this study is to report data of 2041 patients with cryptococcosis that were attended at the Infectious Diseases Hospital F. J. Muñiz over a 30 year-period.

METHODS

Information about demographic and clinical data, survival time and the applied treatment, was taken from the Mycology Unit database. Mycological exams from different clinical samples were performed. Cryptococcal capsular antigen in serum and cerebrospinal fluid was detected through the latex agglutination technique. Cryptococcus isolates were phenotypically identified and the genotype was determined in some of them. Susceptibility tests were carried out following M27-A3 document.

RESULTS

Seventy five percent of HIV+positive patients and 50% of the HIV-negative population were males. Mean ages were 34.1 in HIV+positive patients and 44.8 in the HIV-negative. Cryptococcosis was associated with AIDS in 98% of the cases. Meningeal compromise was seen in 90% of the patients. Although cerebrospinal fluid rendered more positive results, blood culture was the first diagnostic finding in some cases. Cryptococcal antigen showed positive results in 96.2% of the sera samples and in the 93.1% of the cerebrospinal fluid samples. Most of the isolates were Cryptococcus neoformans and belonged to genotype VNI. Minimal inhibitory concentration values were mostly below the epidemiological cutoff values.

CONCLUSIONS

We observed that thanks to a high level of clinical suspicion, early diagnosis, combined therapy and intracranial pressure control by daily lumbar punctures, the global mortality rate has markedly decreased through the years in the analyzed period.

Cryptococcal meningitis initially presenting with eye symptoms in an immunocompetent patient: A case report

Although cryptococcal meningitis (CM) typically occurs in immunocompromised hosts, immunocompetent humans are susceptible to CM. In humans with an intact immune system, CM presents with signs and symptoms typical of meningitis, including fever, headache and neck stiffness. The present study reported the case of a female immunocompetent patient who presented visual blurring in both eyes and bilateral papilledema for ~1 month. Following hospital admission, the patient was diagnosed with optic nerve inflammation and was treated with intravenous methylprednisolone and oral prednisone. However, the initial symptoms failed to improve and the patient developed a headache. The microscopic examination and India ink test performed using the cerebrospinal fluid of the patient showed the presence of Cryptococcus neoformans. Following combined treatment with amphotericin B and fluconazole, the patient made a full recovery with total resolution of the initial symptoms. This case demonstrates that CM in immunocompetent patients may initially include eye symptoms, which may result in a delayed diagnosis of CM.

Visual loss in HIV-associated cryptococcal meningitis: A case series and review of the mechanisms involved

Permanent visual loss is a devastating yet preventable complication of cryptococcal meningitis. Early and aggressive management of cerebrospinal fluid pressure in conjunction with antifungal therapy is required. Historically, the mechanisms of visual loss in cryptococcal meningitis have included optic neuritis and papilloedema. Hence, the basis of visual loss therapy has been steroid therapy and intracranial pressure lowering without clear guidelines. With the use of high-resolution magnetic resonance imaging of the optic nerve, an additional mechanism has emerged, namely an optic nerve sheath compartment syndrome (ONSCS) caused by severely elevated intracranial pressure and fungal loading in the peri-optic space. An improved understanding of these mechanisms and recognition of the important role played by raised intracranial pressure allows for more targeted treatment measures and better outcomes. In the present case series of 90 HIV co-infected patients with cryptococcal meningitis, we present the clinical and electrophysiological manifestations of Cryptococcus-induced visual loss and review the mechanisms involved.

Ventriculoperitoneal shunts for treating increased intracranial pressure in cryptococcal meningitis with or without ventriculomegaly

INTRODUCTION

Cryptococcosis is an opportunistic mycosis, especially in patients that are human immunodeficiency virus (HIV)-positive, and frequently involves the central nervous system.

METHODS

We assessed the potential of ventriculoperitoneal shunting (VPS) in preventing mortality due to uncontrollable intracranial hypertension (ICH) in 15 patients with acquired immunodeficiency syndrome (AIDS)-related cryptococcal meningitis.

RESULTS

After 2 weeks of antifungal therapy consisting of amphotericin B deoxycholate with or without fluconazole, patients with persistent ICH underwent VPS, despite having persistent Cryptococcus neoformans infection. In 12 patients, the uncontrollable ICH was resolved by VPS.

CONCLUSIONS

Patients with cryptococcal meningoencephalitis who have ICH must be considered for VPS even with positive cerebrospinal fluid cultures.

Bilateral optic neuropathy associated with cryptococcal meningitis in an immunocompetent patient

Cryptococcal meningitis is associated with significant morbidity and is rare among immunocompetent patients. Clinical presentation as well as the course of disease is usually indolent which may delay the diagnosis. We present the case of a 52-year-old woman admitted with headaches, vomiting and fatigue for 3 weeks. She was diagnosed with cryptococcal meningitis and treated with antifungal therapy. She was referred for ophthalmological examination presenting with decreased vision in the left eye (OS; count fingers), left relative afferent pupillary defect and bilateral sixth nerve palsy. Funduscopy revealed florid bilateral papilloedema. Cranial MRI showed indirect signs of intracranial hypertension as well as multiple parenchymal lesions and optic nerve sheath enhancement after contrast administration. A ventriculoperitoneal shunt was placed. In spite of the control of intracranial pressure there was a decrease in vision in the right eye (OD) and deterioration of visual fields. Intravenous methylprednisolone was used to reverse optic neuropathy and to prevent OD visual loss.

Posterior reversible encephalopathy syndrome in a child with meningitis presenting with transient visual loss and hypertension

Posterior reversible encephalopathy syndrome (PRES) is a clinico- radiological syndrome characterized clinically by headache, seizures, visual disturbances, vomiting and radiologically by predominant posterior leukoencephalopathy. The authors report an 11-y-old boy with meningitis presenting with transient hypertension and visual loss and MRI finding compatible with the diagnosis of PRES and complete reversal of symptomatology within 10 d. A wide plethora of tests carried out failed to identify the cause of transient hypertension with a probability of this being due to transient autonomic dysfunction.

The Optic Nerve Compartment Syndrome in Cryptococcus-Induced Visual Loss

Visual loss in cryptococcal meningitis has been postulated to be due to papilloedema and/or optic neuritis. A 28-year-old human immunodeficiency virus (HIV)-positive female presented with visual loss, swollen optic discs, and elevated intracranial pressure due to cryptococcal meningitis. Computerised tomographic cisternography and T2-weighted magnetic resonance imaging showed occlusion of the peri-optic subarachnoid space and its reopening after serial lumbar punctures. Presumably lowering of the intracranial pressure resulted in equalisation of pressure across the pressure gradient created by the fungal block. This case supports a third mechanism of visual loss in cryptococcal meningitis, namely, an optic nerve compartment syndrome, that seems more plausible as the principal mechanism.

Early clinical and subclinical visual evoked potential and Humphrey's visual field defects in cryptococcal meningitis

Cryptococcal induced visual loss is a devastating complication in survivors of cryptococcal meningitis (CM). Early detection is paramount in prevention and treatment. Subclinical optic nerve dysfunction in CM has not hitherto been investigated by electrophysiological means. We undertook a prospective study on 90 HIV sero-positive patients with culture confirmed CM. Seventy-four patients underwent visual evoked potential (VEP) testing and 47 patients underwent Humphrey's visual field (HVF) testing. Decreased best corrected visual acuity (BCVA) was detected in 46.5% of patients. VEP was abnormal in 51/74 (68.9%) right eyes and 50/74 (67.6%) left eyes. VEP P100 latency was the main abnormality with mean latency values of 118.9 (±16.5) ms and 119.8 (±15.7) ms for the right and left eyes respectively, mildly prolonged when compared to our laboratory references of 104 (±10) ms (p<0.001). Subclinical VEP abnormality was detected in 56.5% of normal eyes and constituted mostly latency abnormality. VEP amplitude was also significantly reduced in this cohort but minimally so in the visually unimpaired. HVF was abnormal in 36/47 (76.6%) right eyes and 32/45 (71.1%) left eyes. The predominant field defect was peripheral constriction with an enlarged blind spot suggesting the greater impact by raised intracranial pressure over that of optic neuritis. Whether this was due to papilloedema or a compartment syndrome is open to further investigation. Subclinical HVF abnormalities were minimal and therefore a poor screening test for early optic nerve dysfunction. However, early optic nerve dysfunction can be detected by testing of VEP P100 latency, which may precede the onset of visual loss in CM.

Different presentations and outcomes between HIV-infected and HIV-uninfected patients with Cryptococcal meningitis

BACKGROUND AND PURPOSE

Cryptococcus species are the most common causative agents of fungal meningitis. Different populations may show different clinical manifestations and outcomes. In this retrospective study, we investigated these differences in patients with and without HIV infection.

METHODS

From 1995 to 2009, we collected data from HIV-infected or HIV-uninfected patients aged 18 years or over who had cryptococcal meningitis (CM) in a medical center in Taiwan. We reviewed and analyzed their demographic data, clinical manifestations, therapeutic strategies and outcomes.

RESULTS

Among the 72 patients with CM, 19 HIV-infected patients were predominantly younger males, and all of them had AIDS status when CM was diagnosed. In contrast, the 53 HIV-uninfected patients were mostly older males with underlying diseases. The time from initial symptoms to diagnosis was shorter in HIV-infected patients (median 10 vs. 18 days, p = 0.048). The HIV-infected patients presented with less pleocytosis (p = 0.003) and lower protein levels in the cerebrospinal fluid (CSF), but a higher proportion had positive results for cryptococci in the CSF (90% vs. 60%, p = 0.02) and blood (53% vs. 21%, p = 0.009) cultures. Surgical drains and repeated lumbar punctures for the management of increased intracranial pressure were performed in 47% of the HIV-infected patients and 38% of the HIV-uninfected patients. A lower mortality rate was observed in the HIV-infected patients (p = 0.038). On multivariate analysis, initial CD4 count ≤20/mm(3) was an indicator of death or relapse in HIV-infected patients. In the HIV-uninfected group, the initial high cryptococcal antigen titer in the CSF (≥1:512) and hydrocephalus were related to unsatisfactory outcomes.

CONCLUSION

In addition to well-known differences, we found a lower mortality in HIV-infected patients than in HIV-uninfected patients. Cryptococci and inflammation in the central nervous system may play important roles in the pathogenesis of CM. Low intensity of inflammation and effective surgical CSF drains for increased intracranial pressure and cryptococci removal may contribute to lower mortality in HIV-infected patients.