What symptoms may occur in patients with cryptococcal meningitis?

Cryptococcal meningitis is a relatively common fungal infection, but the site of infection is the central nervous system. Generally, patients with cryptococcal meningitis will also have many symptoms, such as headaches, vomiting, etc., and pits can also cause meningitis and other symptoms. Cryptococcal meningitis needs to be treated early to avoid worsening of the disease and the occurrence of intracranial space-occupying lesions.

Cryptococcal meningitis is the most common fungal infection of the central nervous system. It is caused by Cryptococcus neoformans. The main clinical manifestations are subacute or chronic meningitis and meningoencephalitis symptoms such as fever, headache, and vomiting. A small number of patients may show clinical manifestations of intracranial space-occupying lesions. The disease is serious, the treatment course is long, the prognosis is poor, and the mortality rate is high. With the advent of drugs such as amphotericin B and flucytosine, the cure rate of cryptococcal meningitis has reached 60% to 70%, and the combined use of drugs has also shortened the treatment course. Although the incidence of this disease is low, its clinical manifestations are quite similar to those of tuberculous meningitis, so it is often misdiagnosed clinically.

Etiology

The pathogenic bacterium is Cryptococcus neoformans, which is round or oval in shape, covered with a membrane composed of cell wall and capsule. It is widely distributed in nature, such as fruits, milk and soil. It is a conditionally pathogenic bacterium that causes disease when the host's immunity is low. Pigeons and other birds can serve as intermediate hosts, and the incidence of new cryptococcal infection among pigeon breeders is several times higher than that of the general population. The main susceptible population for this disease is those who have used broad-spectrum antibiotics, immunosuppressants, anti-cancer drugs for a long time, received organ transplants, and have leukemia, AIDS, lymphosarcoma, systemic lupus erythematosus, tuberculosis, diabetes, etc.

According to its antigenicity, it can be divided into four serotypes: A, B, C, and D. Most of the strains isolated clinically belong to types A and D, and are distributed globally. Most of the infected people are AIDS patients. Type B and C cryptococci are relatively rare. The vast majority of cryptococcal serotypes in my country are type A.

Clinical manifestations

1) The disease can occur in people of all ages, but is most common in young adults aged 20-40.

2) The onset is insidious and the progression is slow. In the early stages, there may be irregular low-grade fever or intermittent headaches, which may persist and progressively worsen. Immunocompromised patients may present with acute onset, with fever, headache, nausea, and vomiting as the first symptoms. In the late stage, the headache is severe, and may even cause convulsions, decerebrate rigidity, and brain herniation.

3) Neurological examination showed that most patients had obvious neck stiffness and Kernig's sign. A small number of people experience mental symptoms such as irritability, personality changes, and memory loss. Larger granulomas in the cerebrum, cerebellum, or brainstem cause focal signs such as limb paralysis and ataxia. Most patients experience symptoms and signs of increased intracranial pressure, such as papilledema and later optic atrophy, varying degrees of impaired consciousness, and hydrocephalus due to ventricular system obstruction. Due to the obvious exudation of the subarachnoid space at the base of the brain, there is often adhesion of the arachnoid membrane, which causes symptoms of damage to most cranial nerves, often involving the auditory nerve, facial nerve, and oculomotor nerve.

4) Such patients may often have new infections with other bacterial species, or relapses of previous latent bacterial infections in the body, resulting in dual or multiple infection symptoms, commonly accompanied by tuberculosis and/or toxoplasmosis, which makes the condition more serious and complicated, and deserves attention.