A woman’s mysterious illness turns out to be a snake parasite in her brain

A neurosurgeon in Australia removed a roundworm from a woman’s brain 64 years old. Nematodes (also called roundworms) are 7.6 centimeters (3 inches) long. This came as a huge surprise to the team of doctors and infectious disease specialists who treated the woman. They spent more than a year trying to figure out the cause of his recurring symptoms.

That evacuation happened last year. Careful study of the worm clearly shows why the diagnosis is so difficult to pin down: the roundworm is known to infect snakes, particularly pythons endemic to the area where the woman lives, as well as the python’s mammalian prey.The woman is believed to be The first human to be infected with this snake-adapted wormand this is the first time the worm has been discovered Digging into the mammalian brain.

a mysterious disease

When the woman became ill, “trying to identify these never-before-seen tiny larvae that cause infection in humans was like looking for a needle in a haystack,” science professor Karina Kennedy said in a release. . Director of Clinical Microbiology, Canberra Hospital, Australian National University School of Medicine.

The case has been published in the latest issue of Emerging Infectious Diseases, starting in January 2021. The woman presented to a local hospital in southeastern New South Wales, Australia, with a three-week history of abdominal pain, diarrhoea, dry cough, and night sweats.Her blood work showed some kind of infection, the scan showed Symptoms of Pneumonia, and lesions of the spleen and liver. But tests for known microbes and parasites came back negative, as did tests for cancer and autoimmune diseases. He was diagnosed with pneumonia of unknown cause and was treated with the corticosteroid prednisolone.

Three weeks later, he was taken to another hospital with recurring fever and persistent cough. Doctors again found lesions in the lungs, liver and spleen, as well as signs of infection. His blood was high in eosinophils, white blood cells that fight off parasitic infections. She was treated for high eosinophil levels, and she was treated with the antiparasitic drug ivermectin because of concerns about false negatives for roundworm infection in humans.

From mid-2021 to early 2022, the woman’s liver and lung conditions improved. He was able to reduce the dose of prednisolone by adding another drug to help reduce the eosinophil count.

a brain-drilling worm

But soon after, she experienced three months of forgetfulness and mounting depression. An MRI of the brain revealed an expanding lesion in his right frontal lobe. In June 2022, he underwent a biopsy in which neurosurgeons removed the live, twisted parasite from his brain.

Subsequent testing identified the roundworm as Ophidascaris robertsi based on its red color and morphological characteristics. Genetic testing confirmed this identity.

The woman was again given ivermectin and another antiparasitic drug, albendazole. Several months later, her lung and liver lesions improved, and neuropsychiatric symptoms persisted but improved.

Doctors believe woman was infected after searching for sheets WarrigalAlso known as New Zealand spinach, it is located around a lake near her home where carpet pythons inhabit.In general, adults Roberts They live in the snake’s esophagus and stomach, and release their eggs in the feces. From there, the snake’s eggs are collected by the small mammals that the snake eats. The larvae develop and colonize small mammals, and despite the animal’s small size, they grow to be quite large, and the worm’s life cycle is complete when the snake eats the infected prey.

you have to wash the food

Doctors speculate the woman had collected eggs for small mammals while foraging for food and ingested them, either by not washing or cooking the vegetables adequately, or by not washing her hands properly or using kitchen equipment.In retrospect, the progression of her symptoms suggested an initial foodborne infection followed by Maggot larvae migrating from the gastrointestinal tract to multiple organs

. Prednisolone, an immunosuppressive drug, may inadvertently help nematodes migrate and reach the central nervous system.

Kennedy, who co-authored the report on the woman’s case, highlighted wash any food collected or taken from the garden. He also emphasized proper kitchen safety and hand washing.

In the meantime, the woman remains under surveillance. Another co-author, Sanjaya Senanayake of the Australian National University, an infectious diseases physician at Canberra Hospital, praised her management of the infection. “Being the world’s first patient for no reason is anything but easy or desirable. My admiration for this woman who has shown patience and courage throughout this process cannot be expressed enough. “

Article originally published on Ars Technica. Adapted by Mauricio Serfati Godoy.