Lyme disease
Lyme disease can affect the nervous system, causing facial nerve palsy, meningitis, and radiculoneuritis. Diagnosis relies on positive Lyme serologies. Treatment varies based on the neurological manifestation. For facial palsy, oral doxycycline is common. Meningitis and radiculoneuritis may need intravenous antibiotics like ceftriaxone. Lack of response may have various causes and requires reevaluation. Prophylaxis with doxycycline is recommended for specific tick bite situations.
Behçet's syndrome
Behçet's syndrome is characterized by recurrent oral and genital ulcers, along with various systemic manifestations. Neurological issues are rare but can affect the brain tissue or dural sinuses. Treatment depends on severity, with immunosuppressive drugs like azathioprine used for severe cases. Dural sinus thrombosis may require anticoagulation therapy.
Whipple’s disease
Whipple's disease (WD) is caused by T. whipplei bacteria and can affect the central nervous system (CNS). Symptoms vary and can include confusion, cognitive impairment, and abnormal movements. Diagnosis involves brain MRI and T. whipplei PCR on cerebrospinal fluid (CSF). Treatment includes antibiotics followed by long-term oral maintenance therapy. In some cases, corticosteroids may be needed, and patients should be monitored for immune reconstitution inflammatory syndrome (IRIS). Relapses may occur and require additional treatment.
Brain Abscess
Brain abscesses are localized infections within the brain. They are often caused by bacteria, such as Staphylococcus aureus. Diagnosis is made through MRI, and treatment involves antibiotics like penicillin G, metronidazole, ceftriaxone, ceftazidime, and vancomycin, based on the source of the infection. Surgical drainage, either through needle aspiration or excision, is often necessary for diagnosis and treatment, especially in traumatic or fungal cases. Treatment duration varies, with immunocompromised patients needing longer therapy.
HIV Neuropathy
HIV-related neuropathic conditions include distal symmetric peripheral neuropathy (DSPN), often caused by HIV viremia, aging, diabetes, or certain drugs. Treatment involves discontinuing neurotoxic medications, using antiretroviral therapy, and managing symptoms with drugs like gabapentin and duloxetine. Other HIV-related neuropathies include acute and chronic inflammatory demyelinating polyneuropathies, progressive polyradiculopathy, and autonomic neuropathy, though the prevalence of autonomic neuropathy has decreased in the era of antiretroviral therapy.
HIV Myopathy
HIV myopathy is a muscle weakness condition in HIV-infected individuals, often caused by older HIV medications. Treatment typically starts with glucocorticoids like prednisolone or methylprednisolone, followed by a gradual tapering of the medication. Non-responders may try methotrexate or azathioprine. Monitoring for side effects is important. Physical and speech therapy, along with dietary precautions, can also help manage the condition.
CNS Lymphoma
Primary central nervous system lymphoma (PCNSL) is a rare type of brain lymphoma. Diagnosis involves biopsy, and treatment includes high-dose methotrexate with rituximab. Surgery is mainly for diagnosis, and clinical trials are encouraged. Consolidation therapy may involve high-dose chemotherapy or radiation. Relapse can be treated with various options.
Tuberculous Meningitis
Tuberculous meningitis is a serious brain infection linked to tuberculosis, typically affecting young children and adults with weakened immune systems. Symptoms include a stiff neck, headache, fever, and vomiting. Diagnosis is confirmed through cerebrospinal fluid tests. Early treatment with tuberculosis drugs and corticosteroids is crucial. A surgical consultation may be necessary for those with hydrocephalus (increased brain fluid) or vision issues. Patients should be closely monitored and treated with directly observed therapy for 9 to 12 months. Drug-resistant strains require different treatment regimens. Corticosteroids help manage inflammation, and surgery may be considered for certain complications.
CNS Toxoplasmosis
Toxoplasmosis is a brain infection common in immunosuppressed individuals, caused by the parasite Toxoplasma gondii. Symptoms include fever, encephalitis, and eye problems. Treatment involves drugs like sulfadiazine, pyrimethamine, and leucovorin. Corticosteroids may be used for certain symptoms. Improvement is expected in most cases, and treatment lasts about six weeks, with the possibility of long-term therapy. Primary prevention with medication is recommended for some HIV patients.
HIV Dementia
HIV-associated neurocognitive disorders (HAND), including HIV-associated dementia (HAD), involve cognitive impairments in memory, attention, and motor skills. HAD is diagnosed when cognitive deficits in two domains and daily life difficulties are evident. Screening for mild deficits is debatable. Antiretroviral therapy (ART) is the primary treatment, often leading to improvement within weeks to months. In cases with neuropsychiatric features or dementia, adjunctive medications like methylphenidate may be considered, with safety assessments and referrals as needed.
CMV Encephalitis
Cytomegalovirus (CMV) encephalitis is a serious complication often seen in AIDS patients or those with severe immune suppression, potentially leading to paralysis or fatal encephalitis. It can occur even before a significant drop in CD4 cell count. Symptoms include altered mental status, confusion, and neurological issues. Diagnosis is confirmed by detecting CMV DNA or antigen in the cerebrospinal fluid. Treatment involves dual therapy with ganciclovir and foscarnet, or alternative options if needed. Antiretroviral therapy begins after about two weeks of anti-CMV treatment, and maintenance therapy with valganciclovir continues until the CD4 count reaches ≥100 cells/microL for at least six months.
Paraneoplastic myelitis
Paraneoplastic myelitis is a diverse group of spinal cord disorders caused by mechanisms unrelated to metastases, infections, coagulopathy, or metabolic issues. It leads to rapidly progressive spastic paresis and can involve other parts of the nervous system. Commonly associated antibodies include anti-Hu, anti-CRMP5, and anti-amphiphysin antibodies, with a strong association with small cell lung cancer (SCLC) and other malignancies. Treatment focuses on removing the tumor source and suppressing the immune response. Plasma exchange or intravenous immune globulin (IVIG) may be used initially, followed by glucocorticoids, cyclophosphamide, or rituximab if needed. Early tumor identification and management can stabilize or improve the neurological syndrome.
Spinal epidural abscess
Spinal epidural abscess (SEA) is a serious spinal cord infection that can lead to severe complications or death. It can be caused by bacteria entering through various means. Prompt diagnosis with MRI is crucial. Treatment involves surgical drainage and antibiotics. Empiric antibiotics are given immediately upon suspicion, followed by tailored antibiotics once the pathogen is known. Surgery is required for certain cases, while selected patients may be managed conservatively. Treatment typically lasts four to eight weeks.
Acute Transverse Myelitis
Acute transverse myelitis (TM) is a rapid-onset immune-related spinal cord disorder often triggered by viral infections. It can lead to symptoms like weakness, sensory changes, and bladder problems. Treatment includes high-dose glucocorticoid therapy, plasma exchange in non-responsive cases, and supportive care like physical therapy and urinary retention management. Recurrence is possible, and some patients may develop multiple sclerosis, warranting chronic immunomodulatory therapy.
Viral Encephalitis
Viral encephalitis involves viral infection of the central nervous system (CNS). It often presents with altered mental status, motor or sensory deficits, behavioral and personality changes, speech and movement disorders. Viral encephalitis can be primary or post-infectious and is caused by various viruses, including herpes simplex virus type 1, St. Louis encephalitis, Japanese encephalitis, enterovirus type 71, West Nile virus, cytomegalovirus (CMV), varicella zoster virus, Epstein-Barr virus, HIV, human herpes virus-6, and Zika virus.
Autoimmune Encephalitis
Autoimmune encephalitis is an immune-mediated inflammatory brain condition, often linked with antibodies against neuronal cell surface/synaptic proteins. It encompasses a range of syndromes with diverse neuropsychiatric symptoms, including memory deficits, cognitive impairment, psychosis, seizures, abnormal movements, or coma. The condition is related to various antibodies and can be associated with different types of cancers.
Paraneoplastic Encephalitis
Paraneoplastic encephalitis is an inflammatory brain condition related to cancer. It is usually immune-mediated and often associated with antibodies against intracellular neuronal proteins. Manifestations can include limbic, brainstem encephalitis, or widespread neuraxis involvement. It frequently associates with certain autoantibodies and various types of cancer. Symptoms typically include amnesia, confusion, or seizures.