What are the other Names for this Condition? (Also known as/Synonyms)

• Brain Myiasis
• Myiasis of the Brain

What is Cerebral Myiasis? (Definition/Background Information)

• Myiasis is primarily a skin disease caused by several species of parasitic fly larva (of taxonomic order Diptera). The fly larvae (maggots) cause disease in humans and other vertebrate animals by feeding on the tissues. The infection is usually characterized by a painful, itchy, boil-like skin lesion that contains the parasite within it
• Cerebral Myiasis is an extremely rare but potentially lethal form of myiasis that involves the brain. The main risk factor for Cerebral Myiasis is improper care of head trauma or invasive brain procedures that result in head wounds. The pathogen that commonly cause the condition is the cattle grub (Hypoderma bovis)
• Cerebral Myiasis can cause severe signs and symptoms and serious complications, if not immediately addressed. Management of the condition involves removal of all larvae through appropriate surgical methods. Nevertheless, the prognosis of Cerebral Myiasis is generally poor

Who gets Cerebral Myiasis? (Age and Sex Distribution)

• Cerebral Myiasis is an extremely rare condition that usually affects adults, although individuals of any age category may be affected
• Both males and females are affected
• Worldwide, individuals of all racial and ethnic groups may be affected. Among the reported cases, a vast majority are from the developing nations

What are the Risk Factors for Cerebral Myiasis? (Predisposing Factors)

The following are the risk factors for Cerebral Myiasis: (mainly in the endemic regions)

• Open wounds in the head, especially from external trauma or accidents
• Past surgery to the brain (craniotomy)
• Myiasis of the eye, ear, or nasal cavity that affect the central nervous system
• Malignancies of the brain with skin manifestation

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Cerebral Myiasis? (Etiology)

Cerebral Myiasis is a highly uncommon parasitic infection of the brain caused by any of the following species of insect larvae:

• Cattle grub (Hypoderma bovis) - most commonly identified parasite
• Common green bottle fly (Phaenicia sericata)
• Human botfly (Dermatobia hominis)
• Warble fly (Hypoderma lineatum)

The insects may lay their eggs or deposit larvae on preexisting wounds/lesions (that came about from external injury or surgery to the cranium) and find their way into the central nervous system. Alternatively, myiasis from other regions, such as from the face or eyes, may move to involve the brain causing Cerebral Myiasis.

What are the Signs and Symptoms of Cerebral Myiasis?

The signs and symptoms of Cerebral Myiasis are dependent on the brain region that is affected and can be highly variable. The signs and symptoms are often severe and may include:

• Frequent headaches
• Nausea and vomiting
• Vision defects
• Loss of sensation or movement in arms/legs
• Difficulty with balance
• Difficulty with hearing and speech
• Focal motor and sensory neurological deficits
• Intracranial hypertension
• Decreased mental status
• Seizures
• Hydrocephalus
• Extrapyramidal symptoms, such as Parkinsonism, dyskinesia, dystonia, and akathisia, may be noted

In many cases, it is noted that the frontal lobes of the brain are affected

How is Cerebral Myiasis Diagnosed?

Cerebral Myiasis is diagnosed on the basis of the following information. The diagnostic techniques used may vary based on the specific type of causative parasite.

• Complete physical examination and a thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests: Blood tests, such as complete blood count, which may show increased white blood cells
• Neurological examination
• Imaging studies that may include CT and MRI scans of the head and neck
• Angiogram: An angiogram involves injecting dye into the bloodstream, which makes the blood vessels to appear visually on X-rays

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Cerebral Myiasis?

The complications of Cerebral Myiasis may include:

• Severe emotional stress
• Secondary infections
• Severe neurological defects
• Brain infections such as encephalitis and meningitis
• Severe inflammatory response to dead larvae or parts of larvae, especially during its removal
• Sepsis, which can be life-threatening

How is Cerebral Myiasis Treated?

The treatment for Cerebral Myiasis may involve the following measures:

• Surgical excision and extraction of larvae, where feasible
• Prophylactic antibiotics and tetanus therapy
• Oral and intravenous medications, as prescribed

Examination and identification of the larva following removal may be undertaken.

How can Cerebral Myiasis be Prevented?

Cerebral Myiasis may be prevented by considering the following measures:

• Immediately treating all forms of cutaneous myiasis
• Maintaining basic personal hygiene
• Adequate post-operative care at the healthcare institution and at home
• Ensure that wounds and skin ulcers are properly treated and dressed/covered
• Undertaking early treatment for all CNS medical conditions
• Medical centers should provide fly screens on patient area doors, windows, and ventilators
• Use insect repellents to prevent the insects from entering residences
• The growth of adult flies must be effectively controlled and methods for eradication followed on a regular basis

What is the Prognosis of Cerebral Myiasis? (Outcomes/Resolutions)

The prognosis of Cerebral Myiasis varies from one individual to another and depends on several factors such as the location of the parasitic infection in the brain and the health status of the individual. Nevertheless, according to available medical literature, the outcomes are usually poor.

Additional and Relevant Useful Information for Cerebral Myiasis:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/healthy-living/skin-disorders/