Custom Search

       

 

Infectious Disease Online

Pathology of Dirofilariasis

Dr Sampurna Roy MD

 

                                                                                                                      

 

 

 

 

Pulmonary Dirofilariasis:

 

The filarial nematode Dirofilaria immitis, a common parasite of dogs, cats and other mammals, is transmitted by mosquitoes.

In humans the infective stage usually does not reach maturity, but is swept by the venous circulation into the lung, where it obstructs a pulmonary arteriole and causes a subpleural infarct, which resolves as a granuloma.  

Related posts: Filariasis ; Onchocerciasis

Originally reported from Japan and Australia, pulmonary dirofilariasis is most common in the southern and eastern United States.

Most of these lesions are silent and are discovered as spherical, 1cm to 3cm, subpleural "coin lesions" during radiologic examination of the chest.

Microscopically, a central area of coagulation necrosis is surrounded by a zone of granulomatous reaction.

The coiled immature and degenerating Dirofilaria immitis is located in an arteriole in the central zone of necrosis.

Lesion may be resected using video-assisted thoracic surgery (VATS) which appear to be the best method for diagnosing pulmonary dirofilariasis.

Subcutaneous Dirofilariasis:

Dirofilaria tenuis, a subcutaneous parasite of the racoon, and Dirofilaria repens, a subcutaneous parasite of dogs and cats in Europe, Africa, and Asia, cause subcutaneous dirofilariasis in humans.

Each of these species is probably transmitted to humans by mosquitoes.

Before reaching maturity, the infective stage of the worm degenerates and provokes an abscess, usually surrounded by a granulomatous perimeter.

The most common site is the subcutaneous tissue of the trunk, but the conjunctiva, eyelid, scrotum, and breast can also be affected.

Clinically, a subcutaneous tender nodule gradually enlarges for several weeks.

Microscopically, a central abscess contains a single coiled worm.

Older lesions are granulomatous.

The diagnosis is made by identifying the worm in a biopsy.

Image1 ;  Image2 ;  Image3  (Pinterest)

 

Further reading:

Surgery still opens an unexpected bag of worms! An intraperitoneal live female Dirofilaria worm: case report and review of the literature.

Human pulmonary dirofilariasis: a case report and review of the recent Japanese literature.

A case of pulmonary dirofilariasis that required differentiation from nontuberculous mycobacteriosis.

Intravitreal dirofilariasis: a rare ocular infection.

Natural vectors of dirofilariasis in rural and urban areas of the Tuscan region, central Italy.

 

 

Dr Sampurna Roy  MD

Consultant  Histopathologist (Kolkata - India)


 

 

Histopathology-India.net

 

Pathopedia-India.com

 

Surgical Pathology.com

 

Pathology-India.com

 

Dermpath-India

 

Infectious Disease Online

 

Pathology Quiz Online 

 

Paediatric Pathology Online

 

Pancreatic Pathology Online

 

Paraganglioma-Online

 

Endocrine Pathology Online

 

Eye Pathology Online

 

Ear Pathology Online

 

Cardiac Path Online

 

Pulmonary Pathology Online

 

Lung Tumour Online

 

Mesothelioma-Online

 

Nutritional Pathology Online

 

Environmental Pathology Online

 

Soft Tissue Tumour Online

 

GI Path Online-India

 

Gallbladder Pathology Online

 

E-book - History of Medicine  

 

Microscope - Seeing the Unseen

 

 roypath.in

 

 

Disclaimer

Privacy Policy  

Advertising Policy

Copyright 2017  histopathology-india.net