Pulmonary manifestation of Worms Parasitology Department Medical Faculty of USU

DMD2General Pulmonary manifestation of worms can result from:  Nematode larvae:  Ascaris lumbricoides  Ancylostoma spp.  Strongyloides stercoralis  Trematode Larvae:  Paragonimus westermani

Nematode Larvae manifestation

DMD4 Nematode larvae manifestation Life cycle (Ascaris lumbricoides)

DMD5 Nematode larvae manifestation Life cycle (Hookworm)

DMD6 Nematode larvae manifestation Life cycle ( Strongyloides stercoralis)

DMD7 Nematode larvae manifestation Life cycle (Strongyloides stercoralis)

DMD8 Nematode larvae manifestation Pathogenesis Larva penetrate the mucosa enter the lymphatics and venules, migrate to the right heart and lungs, break out into the alveoli, molt twice, ascend the respiratory tree and descend the oesophagus to mature in the intestine. Larvae migrating through the lung can cause eosinophilic inflammation and granulomatous reaction. Mild infections frequently remain inapparent. In more severe infections, larval migration in the lungs provoke hemorrhages and inflammatory infiltrations, which present as diffuse mottling and prominence of peribronchial regions in radiographs

DMD9 Nematode larvae manifestation Pathogenesis This can induce pulmonary hypersensitivity may cause hypersecretion of mucus,serous exudate and bronchiolar inflammation. It may be accompanied by coughing, dyspnea, and mild fever. Sputum can be containing eosinophils or charcot- Leyden crystals. Hookworm larvae and Strongyloides less commonly elicit symptoms of pulmonary eosinophilia if we compare with Ascaris larvae.

DMD10 Charcot leyden chrystals image.

DMD  m500  m 8.7 c Image of nematode larvae in lungs

DMD12 Nematode larvae manifestation Diagnosis Diagnosed by detecting larvae either in respiratory secretions or in gastric aspirates Stool examination will be negative during or soon after an episode of pneumonitis but two or three months later will be positive. This will support worm larvae as the etiologic agent of the pneumonitis.

DMD13 Nematode larvae manifestation Treatment This disease usually self limited and very rarely fatal, specific therapy usually is not necessary. If severe, systemic corticosteroid will be used. Anthelminthic therapy is indicated to eradicate the worm infection to prevent unusual. The drug of choice: –Mebendazole (500mg single dose) –Albendazole (400mg single dose) –Pyrantel pamoate (single dose of 11 mg/Kg, not to exceed 1 gr)

Trematode manifestation

DMD15 Trematode larvae manifestation Life cycle

DMD16 Trematode larvae manifestation Pathogenesis After human ingestion of infected undercooked crabs or crayfish, the metacercariae excyst in the duodenum, penetrate the gastrointestinal wall, and migrate within the peritoneal cavity. Although some young flukes may migrate to extra-pulmonary sites, most of the developing flukes penetrate the diaphragm to migrate within the pulmonary parenchyma.

DMD17 Trematode larvae manifestation Pathogenesis Young and immature flukes can migrate from the peritoneal cavity to organs other than the lung or may migrate from the lungs to reach almost any body site. The parasite can encapsulate in ectopic sites and egg production can follow. The flukes become surrounded by an infiltrate of eosinophils and neutrophils, and later mononuclear leukocytes. Local necrosis of pulmonary parenchyma occurs, followed by the development of a fibrous capsule around the maturing flukes.

DMD18 Trematode larvae manifestation Pathogenesis This worm may invade the lungs and produce pleural effusions or eosinophil- enriched inflammatory infiltrates. By the seventh or eighth week of infection, the completely matured flukes begin egg production within the capsule which may enlarge and rupture, often into a bronchiole.

DMD19 Trematode larvae manifestation Symptoms  The incubation period is 2-20 days after ingestion  As larval migration within the lung parenchyma increases, the patient often experiences an irritating cough, chest pain, and malaise. Less common symptoms include a low grade fever and blood streaked sputum.

DMD20 Trematode larvae manifestation Diagnosis  Presumptive diagnosis by Clinical examination  Peripheral Eosinophilia; early phase of infection; 10-30%  Microscopy: eggs in stool will be positive if the sputum is swallowed, but not in early phase (8-10 weeks)  Serology: ELISA and countercurrent immuno- electrophoresis  Imaging: calcified lung cyst 50% cases); “soap- bubble calcifications) on skull imaging or “grape- cluster” on CT/ MRI

DMD21 Trematode larvae manifestation Therapy  Praziquantel (75 mg/kg/ 3 doses; 2 days)  Triclabendazole (5 mg/kg daily for 3 days or 10 mg/kg twice / one day or 10 mg/kg single dose

House dust mites

DMD23 House dust mites General AstigmataAstigmata Wide variety of habitatsWide variety of habitats Cosmopolitan distributionCosmopolitan distribution Four species have been associated with allergic disease: Dermatophagoides pteronyssinus, D.farines, D. microceras, Euroglyphus mayneiFour species have been associated with allergic disease: Dermatophagoides pteronyssinus, D.farines, D. microceras, Euroglyphus maynei Usually colonized bedding, sofas, carpets, or any woven material.Usually colonized bedding, sofas, carpets, or any woven material. Dust mites do not bite, and aside from causing allergic disease.

DMD24 House dust mites General Mites absorb humidity from the atmosphere and feed on organic matter (including shed human and animal skin particles), usually with the aid of fungal degradation. Mite fecal particles contain a complex mixture of allergenic mite-derived protein, endotoxin, enzymes, and mite and bacterial DNA, all of which can be immuno- stimulatory. These particles are relatively large and heavy. They may become transiently airborne after vigorous disturbance, but then settle rapidly. Three common syndrome: asthma, perennial rhinitis, childhood eczema

DMD25 House dust mites Control Keeping house dry reduces mite densities remove dust by vacuuming expose mattress to sunlight to kill mites and denature mite allergens use plastic mattress covers and replace mattress annually use of miticides

DMD26 House dust mites Control Remove dust mites by vacuuming.

DMD27 Washing mattress using Vax shampoo. House dust mites Control

DMD28 House dust mites Control Sunning of mattress and pillows.