OS 213LEC 13: PARAGONIMUS WESTERMANI

OS 210LEC 0X: TITLE

OS 213: Human Disease and Treatment 3(Circulation and Respiration)LEC 13: PARAGONIMUS WESTERMANIIExam 1 | Dr. Sonia Salamat | 25 January 2013

TransersUPCM 2016: XVI, WalangKapantay!4of 3

\\Mara, Mel, MichUPCM 2016 A: XVI, WalangKapantay!3of 3

OUTLINEI. Paragonimus WestermaniiA. AnatomyB. Life CycleII. VectorsA. Primary HostB. Secondary HostC. Metacercaria

III. ParagonomiasisA. AcquisitionB. Distribution

PARAGONIMUS WESTERMANII Lung fluke Paragonimus westermanii Member of the flatworms, Platyhelminthes and Class Trematoda

Live Worms

Figure 1. Paragonimus westermanii live worm Plump and ovoid 7.5 to 12 mm long Up to 1.2 cm long 5 mm thick 4 mm wile Reddish brown

Anatomy

Figure 2. Paragonimus sp. Adult Lung Fluke.(Key: AC=acetabulum (ventral sucker); OV=ovary; CE=cecum; TE=testes; OS=oral sucker; UT=uterus; EB=excretory bladder) Posterior oral sucker Posterior testes (R and L) Ovary (R and L) Single ventral sucker which is hard to locate Uterus: tightly coiled rosette Vitellaria: bilateral, extensive branching Ceca: wave on side of adult worm

Egg Broadly ovoid Operculum cap-like Opposite the operculum is the abopercular end; this is the thickened area Unembryonated when deposited Golden brown Eggs produced exit feces because we swallow sputum 11B eggs in sputum

Life Cycle

Diagnostic stage is the unembryonated egg Will develop into embryonated egg once in reaches water Miracidia lives within the first intermediate host which is a snail Miracidium as it develops into several larval stages (sporocysts, rediae, cercariae) will undergoe several division. Thus, remember that a miracidium is not really equal to a cercaria. The second intermediate host can vary from crayfish to crabs etc depending on the area. Their common characteristic is that they are all crustaceans. So, it is not species specific. In the Philippines, our second intermediate host is the small crab, Sundathelpusa. Adults reside embedded to the cystic cavities in the lungs eggs excreted in sputum/feces. Does not go through circulation/mesenteric vessels. Instead, they penetrate intestinal wall and peritoneal cavity.

VECTORS

Figure 3. Paragonimus sp. vectors

Primary: Antemelania First intermediate host:the snails Antemelaniaasperata; Antemelaniadactylus Miracidium enters snail one sporocyst stage 2 redial stagecercaria emerges exit snail to infect 20 host Cercaria Covered with spines and has an ellipsoidal body with small tail Stylet present at dorsal side of the oral sucker

Figure 4.Antemelania

Secondary: Sundathelphusa Second intermediate host:mountain crab Sundathelpusaphilippina Cercaria penetrates soft parts Encysts metacercaria in the gills, body muscles, viscera, legs Crab may be infected by eating infected snails

Figure 5. Sundathelphusa

Metacercaria Definitive host(man) acquires infection by eating raw or insufficiently cooked crabs harboring metacercaria Metacercaria is round and measures from 381-457 micrometers After ingestion, metacercaria excysts in duodenum of host Cysteine proteinases secreted by metacercarias excretory bladder help in excystment and host immune modulation Adolescent worm then penetrates the intestinal wall, into the peritoneal cavity, where it wanders about and embeds itself in the abdominal wall for several days Afterwards, returns to coelom, migrates through diaphragm to pleural cavity and into the lungs where it becomes encapsulated and develops into adulthood Completion of development in the definitive host: 65-90 days Can persists in man up to 20 years or more Can also infect dogs, cats, rats

PARAGONOMIASIS Lung fluke disease that must be differentiated from TB, which presents with similar symptoms. The two diseases may occur simultaneously (Great mimic of TB). Zoonotic infection An emerging food-borne parasitosis caused by Paragonimus spp. A trematodiasis, or fluke infection, which is among the neglected tropical diseases (NTDs) according to WHO. NTDs are old diseases which have been around for quite some time but have been neglected because: 1) there is no program to address them, 2) there is no budget, and 3) they are not prioritized because of the general thinking that they are rare. History of ingestion of inadequately raw, cooked or pickled crustaceans, abdominal pain, nausea, vomiting, diarrhea, testicular pain, and/or CNS manifestations are reported findings. Patients may develop significant hemoptysis or extensive pulmonary infiltration comparable to PTB infection. Demonstration of lung fluke eggs on sputum examination remains as the gold standard in diagnosis. If you want to examine you have to look for the stool na may eggs When they are mature enough, it will go out Public health and economic impact of paragonimiasis are considerable in terms of: Morbidity (people remain sick for a long time because of misdiagnosis), Loss of productivity (no work, no school), Absenteeism from work and school, Health care costs (paying up for anti-TB drugs when in fact, there is no TB at all), and Agricultural losses (those usually afflicted live in agricultural areas) (WHO, 1995)

Acquiring Paragonimiasis Eating raw crustaceans Marinate crustaceans in brine/rice wine and then eat Eating only salted crustacean Contaminate fingers and utensils with metacercariae while cooking Poor food preparation and handling

Distribution in the Country Considered as endemic in the country Davao, Davao Oriental, Leyte, Samar, Sorsogon, Camarines Norte, Camarines Sur, Cotabato, Basilan, Mindoro, Zamboanga del Norte 16.3% Pulmonary TB patients in Sorsogon were infected with Paragonimus (1999) Symptomatology same as TB Worldwide population rise: 292 x 106 Sources: freshwater crab, crayfish, wild boar meat (as seen in North America)

Symptoms Productive cough Hemoptysis, dyspnea Chest and back pain Fever, anorexia, weight loss Easy fatigability, weakness Paragonimus and TB cannot be differentiated clinically

Chest X-Ray Findings Lung infiltrates Nodules Calcifications Pleural thickening Pleural effusion These can also be found in TB or other cases

Extrapulmonary Organs affected by Paragonimus Liver Intestinal Wall Mesenteric Lymph Nodes Muscles Testes Brain (when infected, can result in granuloma formation with eggs) Peritoneum Pleura

Diagnostic Tests Microscopic exam of sputum and stool Antibody detection (serology/immunology) but not available in the Philippines Histopathology (Biopsy) of brain involvement Future diagnostic tests: Biomarkers Molecular Bio Approaches Serologic Tests ELISA Complement fixation Immunoblot Indirect Hemaglutination Test Other tests Intradermal Skin Testing Other Imaging Procedures (not definitive): CT and MRI Necessary to do multiple diagnostic tests especially for extrapulmonary cases

Treatment Drug of Choice: Praziquantel 25 mg/kg three times daily for 2-3 days, free from DOH provided you have a positive sputum smear for Paragonimus. Effective against pulmonary paragonimiasis and all forms of ectopic infection.

Table 1. High cure rates (Harinasuta & Bunnag, 90; Keiser and Utzinger, 04):TreatmentCure Rate

1 day71.4%

2 days89.5%

3 days100.0%

If there is pleural effusion, drainage must be performed prior to praziquantel treatment (Nakamura-Uchiyama et al., 2002). Praziquantel can be obtained free from DOH. Positive test results needed to obtain the drug. Unfortunately, since Praziquantel is also drug of choice for schistosomiasis, we are rapidly depleting the supply for schistosomiasis treatment programs along the way.

Follow up of Treated Patients Repeat sputum exam 90 days after treatment. Lung fluke infection demonstrated even after treatment may be due to: Heavy lung fluke burden or heavy intensity of infection that may need re-treatment Possibility of re-infection that will require diagnosis and re-treatment: 10-12% reinfection rate after 1-2 years

Alternative drugs: Bithionol and Trielabendazole (not available in the Philippines) Adjunctive treatment Anticonvulsants (for extrapulmonary and brain) Steroids (to decrease swelling) Decompress cranial pressure Surgery not first treatment of choice

Treatment Using Other DrugsTriclabendazole This is now the drug of choice according to WHO. 10 mg/kg for two doses in a single day (WHO, 2004) 10 mg/kg single dose: high cure rates, better tolerated than praziquantel, better compliance (Calvopina, 1998) Not available here because Switzerland company of triclabendazole wants to know how many patients of paragonimiasis are here in the Philippines, but we cannot give them a number.

Paragonomiasis: A Continuing Problem Discharge of human excreta water contamination leading to infection of snails and crustaceans Consumption of undercooked food (cultural practices, social economics) Poverty For people from developed countries: Travel patterns, Exotic food

Prevention Early diagnosis and appropriate treatment Capability building in public health and TB laboratories especially in known endemic areas Control of intermediate hosts may not be feasible Abstaining from eating raw, freshly salted, or inadequately cooked crabs or crayfish Boiling and frying of infected crustaceans Cook food well Chemotherapy To stop cycle Improved access to Sanitation Infection Education Committee Integrated control

END OF TRANSCRIPTION

Greetings:

Mara: Thank you Katha for your notes.

Mel: Benign week is so benign! 2 modules to go before vacation! And because I havent been greeting the past transes we had, here goes my long greet: Hello to the very awesome GABA! When will we do our Level 7 Bonding: Church Hopping? Congrats to the Concepcions for the Paeng-like bowling prowess, Fres and her Fres ball and Hannah The Striker Co. Thank you for being our awesome adviser, Rae! Lets go to Binondo next weeeeeeek! Hello Aca and Patti! Hi Royce (binigay ko kay Banzweezee yung lumpia. Hihi zorrehh)! Hi seatmates forever Jay-v, Ivan, Regina! Caffeina ulit next week? Hi Vince! Hi elective-mates sa Forensic Patho! And hello Mara and Mich!!! TransersUPCM 2016: XVI, WalangKapantay!3of 3

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