QuestionSBA
QuestionChoice
IVIG and plasmapharesis may be used to treat PML which does not typically cause ring enhancing lesions.
10015824
d
Treat with IVIG and plasmapheresis
QuestionChoice
LP may be contraindicated due to increased intracranial pressure and in the context of HIV neurocomplications is more likely to be a part of the workup for cryptococcal meningitis.
10015823
c
Perform a therapeutic lumbar puncture
QuestionChoice
Toxoplasmosis serology in the blood has no diagnostic bearing on whether cerebral toxoplasmosis exists and is often falsely positive.
10015825
e
Send off toxoplasma serology
QuestionChoice
This case describes a most likely case of toxoplasmosis due to the neuroimaging findings as multiple ring enhancing lesions in HIV are virtually diagnostic of toxoplasmosis. This is the correct answer, as treating toxoplasmosis often involves medical management and monitoring to see whether imaging and symptoms improve. Folate is often co-adminstered with sulfadiazine as it can lead to folate deficiency.
10015821
a
Administer sulfadiazine and pyramethamine
QuestionChoice
Brain biopsies are very invasive and are associated with a host of complications, dexamathesone should be avoided for two reasons, there is very little mass effect and oedema in this case and it could cause an improvement in imaging and confoundthe picture of whether the treatment is working.
10015822
b
Administer dexamethasone and arrange urgent brain biopsy
QuestionComment
QuesNeuroConsultantMed
33418
QuestionComment
u just made my day 
62316
User
subscriber
Nightshift Prone
User
subscriber
Camiodarone
QuestionComment
Stop asking for "appropriate course of action" and specify whether you want the diagnosis or the treatment!
34354
QuestionComment
why so butthurt
44746
User
subscriber
Viral Myopathy
User
subscriber
Epidermis Abdominal
QuestionComment
how do you know this is not cryptococcus neoformans? 
51394
QuestionComment
its just ring enhancing lesions is toxo buzzword, cryptococcus is non-enhancing i think
60141
User
subscriber
Serotonin Myopathy
QuestionComment
does not cause ring enhancing cns lesions
60645
User
subscriber
KO KAVA
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NICU Ketone
Concept
Chapter
# Summary
 

Neurological differentials in HIV encompass a range of neurological disorders that may occur in individuals with HIV, due to the direct viral effects or secondary to opportunistic infections or malignancies. Key conditions include stroke, meningitis, toxoplasmosis, primary CNS lymphoma, progressive multifocal leukoencephalopathy (PML), cytomegalovirus (CMV) encephalitis, and HIV-associated neurocognitive disorder (HAND). Primary identification hinges on clinical signs and symptoms, supplemented by diagnostic investigations such as lumbar puncture, neuroimaging, and laboratory tests. Management strategies primarily involve antiretroviral therapy, condition-specific medications, and supportive care.
 

# Definition
 

Neurological differentials in HIV are neurological conditions that may present in HIV-positive individuals. These may be directly caused by the virus, arise from the immunocompromised state induced by HIV, or occur as a side-effect of antiretroviral treatment.
 

# Epidemiology
 

Neurological complications in HIV are common and can occur at any stage of the disease. They affect a significant portion of individuals living with HIV, with incidence increasing as the disease progresses and the immune system becomes further compromised.
 

# Aetiology
 

The aetiology of neurological differentials in HIV varies, with factors including the direct effects of the HIV virus on the nervous system, the secondary effects of a weakened immune system that allow opportunistic infections and malignancies, and side effects from antiretroviral therapy.
 

 

# Differential Diagnosis
 

|   | **Clinical features**  | **Diagnostic tests**  | **CD4 count** (cells/microlitre) |
|---|---|---|---|
|**Ischaemic stroke**   |Acute-onset symptoms including facial weakness, speech abnormalities, leg weakness, focal neurology   | CT head: hypoattenuation, loss of grey-white matter differentiation, hyperattenuation in an artery   |
|**Meningitis**   |Headache, neck stiffness, photophobia, systemic features (subacute symptoms are more likely to be due to Cryptococcal meningitis which presents in immunocompromised people)   | Lumbar puncture*  | Cryptococcal meningitis <200 |
| **Cerebral toxoplasmosis**  |Focal neurology, visual changes, altered mental status, headache   | Serology positive; CT/MRI: ring-enhancing lesions involving the basal ganglia | <200 |
| **Primary CNS lymphoma** | Headaches, focal neurology, seizures, visual changes | CT/MRI: classically homogenous appearance, but variable especially in immunocompromise | <100 |
|**Progressive multifocal leukencephalopathy**| Altered mental status, motor deficits, ataxia, visual changes, seizures | CT/MRI: asymmetric periventricular & subcortical involvement |
| **CMV encephalitis**| Altered mental status, focal neurology, meningism | MRI: T2/FLAIR non-specific increased signal in white matter; lumbar puncture consistent with viral meningitis* | <100 |
| **HIV-associated neurocognitive disorder**|Progressive cognitive impairment ranging from mild cognitive impairment to HIV-associated dementia |Neurocognitive testing abnormal; CT/MRI normal| <100 |



 

# Investigations
 

Diagnostic investigations depend on the suspected condition and may include:
 

 - Lumbar puncture, which is particularly useful in meningitis
 - Blood tests including serology for toxoplasmosis
 - Glucose measurement, especially in acute presentations
 - Neuroimaging (CT, MRI)
 - Biopsy in selected cases
 - HIV viral load and CD4 count
  
*Lumbar puncture in meningitis: differentiating features

|   | **Appearance**  | **Predominant cell type**  | **Culture**  | **Protein**  | **Glucose** |
|---|---|---|---|---|---|
| **Bacterial meningitis**  | Clear or turbid  | **Polymorphonuclear** cells (i.e. neutrophils)  | Positive  | Raised  | **Reduced** |
| **Aseptic (viral) meningitis**  | Clear or slightly turbid  | **Lymphocytes**  | Negative  | Raised  | **Normal** |
| **Tuberculous meningitis**  | Clear or slightly turbid, fibrin web  | **Lymphocytes** + polymorphonuclear cells  | Negative gram stain; acid-fast bacilli positive (auramine staining)  | Raised  | **Reduced** |

N.b. **Cryptococcal meningitis** may give any of the above results, so should be considered as a differential in any HIV or immunocompromised patient. Classically the opening pressure is very high, and this is a poor prognostic sign. If suspected, request **cryptococcal antigen** or **India Ink** staining.

# Management
 

Management depends on the specific neurological condition, but in general, the following strategies may be employed:
 

 - Initiation or optimization of antiretroviral therapy (ART)
 - Condition-specific medications
  - Ischaemic stroke: antiplatelet therapy & risk factor modification
  - Meningitis: antibiotics, antivirals or antifungals (for cryptococcal meningitis: amphotericin B and a 2nd agent)
  - Cerebral toxoplasmosis: pyrimethamine, sulfadiazine and calcium folinate
  - CMV encephalitis: ganciclovir and foscarnet
 - Supportive care (pain management, physiotherapy, occupational therapy)
 - Neuropsychological support in cases of cognitive impairment

# NICE guidelines

[NICE CKS: Meningitis - bacterial meningitis and meningococcal disease](https://cks.nice.org.uk/topics/meningitis-bacterial-meningitis-meningococcal-disease/)

[NICE: meningitis (bacterial) and meningococcal disease: recognition, diagnosis and management](https://www.nice.org.uk/guidance/ng240/resources/meningitis-bacterial-and-meningococcal-disease-recognition-diagnosis-and-management-pdf-66143949881029)

[NICE CKS: Scenario: Established HIV infection](https://cks.nice.org.uk/topics/hiv-infection-aids/management/established-hiv-infection/)

# References

[Lancet Neurology: HIV infection and stroke: current perspectives and future directions](https://pmc.ncbi.nlm.nih.gov/articles/PMC3460367/#:~:text=Between%201%25%20and%205%25%20of,cerebral%20ischaemic%20lesions%20at%20autopsy.&text=There%20was%20little%20correlation%20between,in%20series%20that%20assessed%20this.)

[Immunity, Inflammation and Disease: Neurological disorders in HIV: hope despite challenges](https://onlinelibrary.wiley.com/doi/full/10.1002/iid3.591)

[BMJ Best Practice: Overview of meningitis](https://bestpractice.bmj.com/topics/en-gb/111?q=Overview%20of%20meningitis&c=suggested)

[BMJ Best Practice: Toxoplasmosis](https://bestpractice.bmj.com/topics/en-gb/557)

[BMJ Best Practice: Assessment of HIV-related mental status changes](https://bestpractice.bmj.com/topics/en-gb/900)

[BMJ Best Practice: Encephalitis](https://bestpractice.bmj.com/topics/en-gb/436)

[BMJ Best Practice: Ischaemic stroke](https://bestpractice.bmj.com/topics/en-gb/3000114)

[BMJ Best Practice: Fungal meningitis](https://bestpractice.bmj.com/topics/en-gb/541)

[Radiopaedia: Lymphomas of the central nervous system](https://radiopaedia.org/articles/lymphomas-of-the-central-nervous-system?lang=gb#nav_clinical-presentation)

[Radiopaedia: Immunodeficiency-associated CNS lymphomas](https://radiopaedia.org/articles/immunodeficiency-associated-cns-lymphomas?lang=gb#nav_radiographic-features)

[Radiopaedia: Progressive multifocal leukencephalopathy](https://radiopaedia.org/articles/progressive-multifocal-leukoencephalopathy?lang=gb#nav_radiographic-features)

[Radiopaedia: Cytomegalovirus encephalitis](https://radiopaedia.org/articles/cytomegalovirus-encephalitis?lang=gb#nav_radiographic-features)
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Neurological differentials in HIV
Topic
27
Genitourinary medicine
Condition
322
Human immunodeficiency virus
UkmlaTopic
13
Infection
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Neurological presentations in HIV positive patients should prompt consideration of toxoplasmosis with characteristic neuroimaging features of multiple ring enhancing lesions.
A 38-year-old HIV positive man comes to the emergency department with headache and fever for the last two days. He denies neck stiffness and photophobia. A CT Head shows multiple ring enhancing lesions with no mass effect.

What is the most appropriate course of action?
a