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

• Myiasis of the Tracheopulmonary Region

What is Tracheopulmonary 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
• Tracheopulmonary Myiasis is an extremely rare form of myiasis involving the trachea (windpipe), bronchus, and/or lungs, due to infestation by fly larvae or eggs. The condition may manifest as whooping cough, severe respiratory distress, and hypoxia (absence of sufficient oxygen supply to the body tissues). The main causative agents for infection are rodent bots (Cuterebra sp.)
• Tracheopulmonary Myiasis can cause severe and extensive tissue destruction and serious complications, if not immediately addressed. Management of the condition involves removal of all larvae followed by surgical debridement of necrotic tissue, if necessary. The prognosis of Tracheopulmonary Myiasis depends on its severity, but is mostly good with early appropriate treatment

Who gets Tracheopulmonary Myiasis? (Age and Sex Distribution)

• Tracheopulmonary Myiasis is a highly uncommon condition that is observed in individuals of a wide age range (both children and adults have been affected)
• Both males and females are affected; but, many cases are reported among males
• Worldwide, individuals of all racial and ethnic groups may be affected. Few of the cases are reported from USA, while isolated cases from Canada, Japan, Brazil, Korea, and Oman, have been recorded

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

The predisposing factors for Tracheopulmonary Myiasis include: (mainly in the endemic regions)

• Myiasis of the nasal cavity or throat (upper respiratory) region that moves to involve the tracheopulmonary region
• Tracheostomy surgical wounds that are left uncared for
• Open wounds in the throat or chest region that are left neglected
• Chronic foul-smelling discharge from the nose or mouth
• Frequent contact with sheep, goats, horses, and other animals
• Poor personal hygiene
• Living in poverty and overcrowded unclean surroundings, low socioeconomic status
• Alcoholism and drug addiction
• Immunocompromised status
• Bedridden patients who cannot care for themselves

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 Tracheopulmonary Myiasis? (Etiology)

Tracheopulmonary Myiasis is a parasitic infection caused by the following parasitic fly larvae:

• Bot fly (Alouattamyia baeri)
• Horse bot flies (Gasterophilus sp.)
• Megaselia spicularis
• Rodent bots (Cuterebra sp.) - most common causative parasite
• Sheep bot fly (Oestrus ovis)

The parasitic insects either lay eggs or deposit their larvae in open wounds. In some cases, the condition may develop from ingestion/inhalation of the eggs/larvae.

What are the Signs and Symptoms of Tracheopulmonary Myiasis?

The signs and symptoms of Tracheopulmonary Myiasis may vary from one individual to another and may also depend on the type of causative larva species. The signs and symptoms may include:

• Whooping cough
• Blood in sputum
• Nasal discharge that is foul-smelling
• Chest pain
• Difficulty in speaking, hoarse voice
• Difficulty in breathing
• Respiratory distress

How is Tracheopulmonary Myiasis Diagnosed?

Tracheopulmonary 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
• Oral and ENT examination
• Laboratory tests: Blood tests, such as complete blood count and peripheral blood smear
• Sputum cytology
• Chest X-ray
• Imaging studies of the head and neck region
• Bronchoscopy

A differential diagnosis to eliminate other conditions/infections may be considered, before arriving at a definitive diagnosis.

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 Tracheopulmonary Myiasis?

The complications of Tracheopulmonary Myiasis can be significant and may include:

• Severe emotional stress
• Secondary infection of the pulmonary region
• Infestation of the bronchus and pleural membranes
• Severe respiratory distress
• Hypoxia
• Hypereosinophilia and leukocytosis (increased white blood cells)
• Severe inflammatory response to dead larvae or parts of larvae, especially during its removal
• Sepsis, which can be life-threatening

How is Tracheopulmonary Myiasis Treated?

The treatment of Tracheopulmonary Myiasis may involve:

• Manual removal of the maggots by visualization through imaging scopes
• Surgical extraction of the maggots may be undertaken if necessary, followed by surgical debridement of necrotic tissue
• Administration of broad-spectrum antibiotics

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

How can Tracheopulmonary Myiasis be Prevented?

Tracheopulmonary Myiasis may be prevented by considering the following measures:

• Immediately and aggressively treating all forms of ENT or cutaneous myiasis
• Maintaining good personal and body hygiene
• Handwashing with soap and water before handling food/meat or eating
• Maintain basic personal and community hygiene and proper sanitation is highly important, particularly in the endemic zones
• Wearing gloves while handling sick or dead animals
• Taking steps to rear healthy farm animals, such as by vaccinating the herd and cleaning sheds regularly
• Quarantining infected herds and eliminating them from the healthy stock of animals
• Undertake prompt treatment and care of any throat or chest wounds (such as surgical or trauma wounds)
• Stop drug abuse and limit alcohol intake
• The growth of adult flies must be effectively controlled and methods for eradication followed on a regular basis

Individuals with compromised immunity are strongly recommended to avoid handling farm animals or hold similar occupations.

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

The prognosis of Tracheopulmonary Myiasis may vary from one individual to another depending on its severity. However, in many cases, the prognosis is good with early diagnosis and treatment (removal of all larvae).

• Extensive tissue destruction with involvement of the respiratory system and delayed/inadequate treatment may result in severe complications
• In some individuals, rupture of an abscess containing the larva may lead to a severe inflammatory response

Additional and Relevant Useful Information for Tracheopulmonary Myiasis:

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

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