Extra-intestinal Cestodes PDF
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Jaurigue, Lamano, Fortuno
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This document presents information on extra-intestinal cestodes, covering Echinococcus and Spirometra. It details the life cycles, differences between species, and clinical manifestations. The content appears to be lecture notes or study material, suitable for medical or biology undergraduate students.
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MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes OUTLINE • • I. Echinococcus spp. o A. Echinococcus granulosus II. Spirometra spp. Family Taeniidae Order Cyclophyllidea Echinococcus spp. • Echinococcus granulosus grum v0 the • Only two can infect humans. • Echinoco...
MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes OUTLINE • • I. Echinococcus spp. o A. Echinococcus granulosus II. Spirometra spp. Family Taeniidae Order Cyclophyllidea Echinococcus spp. • Echinococcus granulosus grum v0 the • Only two can infect humans. • Echinococcus multilocularis • These are all zoonotic, originally it infects animals and is only accidental for humans. • Echinococcus vogeli • Echinococcus oligarthus PARTS Pyriform scolex – the head. Short neck 3 proglottids The uterus is midline (middle), with lateral evaginations, and is filled with eggs which resemble those of other taeniid worms. Echinococcus is rare. CLINICAL MANIFESTATION The larval stage, called HYDATID CYST, Cysts may grow at rates ranging from 1 to Numerous protoscolices may be found is formed through central vesiculation. 5 cm in diameter per year. within the cyst. In echinococcus you can be asymptomatic but after 8 years the symptoms will manifest wherein the cyst is already big. Bigger cyst will be removed surgically and it is toxic for our body and possible that you can have serious anaphylaxis. Inter host : sheep goat horses camels a A. Echinococcus granulosus LIFE CYCLE 1 This resides in the intestine and the gravid proglottids will release eggs. 2 After releasing embryonated eggs, the eggs will hatch in the small intestine then release oncospheres and it will penetrate the intestinal wall. 3 After the oncospheres hatches and penetrates the intestinal wall, it enlarges producing protoscolices and daughter cyst. 4 After that, the definitive host becomes infected by ingesting the cyst (e.g., in dogs, when they ingest this, they will become infected). 5 Lastly, it will invaginate to the intestinal mucosa then eventually it will develop again into an adult after 32 to around 80 days. How are humans infected? Where does it reside?/Organs affected Humans are aberrant intermediate hosts and they become • Liver – 70% infected by ingesting the egg, oncospheres releasing their • Brain – 10% intestine and hydatid cyst develop in a variety of organs. • Lungs – 20 – 30% Can be detected with the use of X-ray test. Incist rupture deliberated protoscolices may create secondary cysts in other sites within the body. DEFINITIVE HOST INFECTED ORGAN LENGTH PROGLOTTIDS GRAVID PROGLOTTID (IS WHERE AN EMBRYO RESIDES) DIFFERENCES Echinococcus granulosus Dogs Liver 2 – 11 mm 4 – 6 in no. With eggs Echinococcus multilocularis Cats Lungs/Alveolar 1.2 – 4.5 mm 2 – 6 in no. With eggs The Echinococcus multilocularis has the same cycle of Echinococcus granulosus. HYDATID CYSTS PROTOSCOLICES • Usually measure 1 to 7 in diameter. • The cyst has an outer laminated hyaline layer and an inner nucleated germinal layer. May be found in brood capsules, which contain only the germinal layer, and daughter cysts which are replicas of the mother cysts. Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes BROOD CAPSULE May rupture and release protoscolices. Cyst → Oncospheres → Egg → Adults Protoscolices and brood capsules that lie free in the cyst are referred to as HYDATID SAND. Up to 2 million protoscolices may be found in an average cyst. There are hydatid cysts that are gross that can be seen in the operating room. INFECTION OF E. granulosus DOWN-REGULATION OF INFLAMMATORY CYTOKINES Recent studies in mice have shown that infection with E. granulosus leads to down-regulation of inflammatory cytokines, resulting in local immunosuppression. This may be the mechanism by which the parasite is able to escape host cell-mediated response. The parasite copies our own immune system so our cells cannot detect them and cannot attack. They hide from the attackers or defense mechanisms of our immune system. ILLUSTRATIONS/DIAGRAMS LIFE CYCLE OF Echinococcus granulosus LIFE CYCLE OF Echinococcus multilocularis (ALVEOLAR ECHINOCOCCOSIS) Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes DIFFERENCES BETWEEN E. granulosus AND E. multilocularis ADULT ECHINOCOCCUS HYDATID CYST DEVELOPMENT Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes This is the picture of the hydatid cyst in our slides or microscopically. HYDATID CYST PARTS HYDATID CYST CYCLE Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes HYDATID SAND UNDER THE MICROSCOPE F- ATROPHY AND NECROSIS HEPATIC CYSTS CYSTS *ABDOMINAL CYSTS PERIBRONCHIAL CYSTS SPUTUM JACKSONIAN EPILEPSY RENAL INVOLVEMENT • • • • • TISSUE grams whim 3 E. multi come PATHOGENESIS AND CLINICAL MANIFESTATIONS Mass effect brought about by the enlarging cyst results in organ impairment as the neighboring tissues undergo atrophy and tissue necrosis. Are mostly found in the inferior right lobe, and may present as: • Hepatic enlargement – largement of the liver • Right epigastric pain • Jaundice – yellowish appearance of the skin and eyes. May rupture from coughing, muscle strain, trauma, aspiration, and operative procedures. • It is possible when the person is unaware that they have hydatid cysts. PROTOSCOLICES, BROOD When this happens, the protoscolices, brood capsules, CAPSULES, AND and daughter cysts may metastasize and reach other DAUGHTER CYSTS tissues to develop into secondary cysts after 2 to 8 years. INTRATHORACIC Cysts may also become intrathoracic if they are located in the superior lobe of the liver and rupture into the thoracic region. • It make travel and reside on other organs INTERMITTENT JAUNDICE, The rupture of a hepatic cyst into the biliary duct produces a FEVER, AND EOSINOPHILIA characteristic triad of findings: intermittent jaundice, fever, and eosinophilia. • Eosinophils - reddish-orange granules, rarely seen in blood picture but it is high whenever a parasitic infection is present. May cause discomfort when the cysts are large enough. May discharge into a bronchus and result in sudden coughing accompanied by allergic symptoms. May contain frothy blood, mucus, hydatid fluid, and bits of membrane. Involvement of the brain may cause increased intracranial pressure and Jacksonian epilepsy. • Saglit lang, parang na kuryente lang yung brain, not same with the usual epilepsy na matagal. May cause intermittent pain, hematuria, kidney dysfunction, and hydatid material in the urine. SECONDARY INFECTION OF THE CYST tilted pocket Secondary infection of the cyst may also occur. → pus of fluid Bacteria may enter the cyst and lead to pyogenic abscess formation. A patient with this condition usually presents with chills and high fever. Secondary cysts and infected cysts result in higher mortality rates.* - in liver WHEN PRIMARY CYSTS RUPTURE In cases where primary cysts rupture, serious anaphylaxis may result from a large amount of hydatid material entering the bloodstream. ↳ defect in IgE Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes • • Multiple cysts on different major organs, seen in 20 to 40% of infected individuals, may consequently result in multiorgan failure. Intrabiliary rupture of the cyst is the most common complication, followed by suppuration. DIAGNOSIS Radiographic findings and/or ultrasonography, combined with a history of residence in an endemic area, and close association with dogs are important in the diagnosis of echinococcosis. • Can be seen with CT SCAN, X-RAY but will not be seen on stools since it is extraintestinal. WHO CLASSIFICATION FOR HEPATIC ECHINOCOCCAL CYSTS The World Health Organization (WHO) has developed a standardized classification system for hepatic cysts detected by ultrasonography. CLASSIFICATION TYPE CL TYPE CE1 TYPE CE2 TYPE CE3 TYPE CE4 TYPE CE5 Table for the WHO Classification for Hepatic Echinococcal Cysts DESCRIPTION Unilocular cystic lesion(s) with uniform anechoic content without pathognomonic signs. Unilocular cysts with uniform anechoic content and with pathognomonic signs that include visible cyst wall and ‘snow flake sign.’ Multivescular, multiseptated cysts. Anechoic content with detachment of laminated membrane from the cyst wall visible as floating membrane or as ‘water-lily sign.’ Heterogenous hypoechoic or hyperechoic degenerative contents, no daughter cysts present. Cysts characterized by thick calcified wall which is arch-shaped, producing a cone-shaped shadow, the degree of calcification may vary from partial to complete. HOW TO TEST IT? Positive serologic tests, such as the use of: • Indirect hemagglutination (IHA), • Indirect fluorescent antibody (IFA) test, and • Enzyme immunoassays (EIA) are adjunct to radiologic. • • • A negative finding, on the other hand, will also not completely rule out the disease since some cyst carriers have undetectable antibodies. o Since it is dormant, it is asymptomatic. Some cyst carriers have undetectable antibodies (hindi lalabas sa serum blood). Serology may have a relatively HIGH sensitivity (80-100%) and specificity (88-96%) if cysts are located in the LIVER, but when cysts are located in OTHER ORGANS such as the lungs and the brain, the serodiagnostic reactivity is LOWERED, decreasing the reliability of this adjunctive diagnostic test. GOLD STANDARD SEROLOGY FOR HUMAN CYSTIC ECHINOCOCCOSIS Detection of IgG antibodies to hydatid cyst fluid-derived • Through ELISA or immunoblot. native or recombinant antigen B subunit. SURGICAL RESECTION CHEMOTHERAPY WITH BENZIMIDAZOLE COMPOUNDS ALBENDAZOLE OR MEBENDAZOLE PERCUTANEOUS ASPIRATION, INJECTION, RE-ASPIRATION (PAIR) TECHNIQUE TREATMENT Is still considered the preferred treatment for echinococcosis presenting with a large (>10 cm in diameter) liver cyst, secondary infection, or cysts in extrahepatic sites. Small (<7 mm in diameter), isolated cysts, uncomplicated cysts, and patients with negative serology respond best to chemotherapy with benzimidazole compounds. Treatment with albendazole (10-15 mg/kg/ day) or mebendazole (40-50 mg/kg/day) for a minimum of three months has been demonstrated to be effective. • May be indicated for patients with single or multiple cysts in the liver, abdominal cavity, spleen, kidney, or bones, who cannot undergo surgery. • Involves: o Ultrasound-guided percutaneous puncture; o Aspiration of substantial amounts of cystic fluid; Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes Injection of a protoscolicidal agent (e.g., 95% ethanol or hypertonic saline) for at least 15 minutes; o Re-aspiration. Has been shown to have greater efficacy and lower rates of morbidity, mortality, and disease recurrence. o PAIR plus ALBENDAZOLE OR MEBENDAZOLE PREVENTION Dogs should not be allowed in slaughterhouses, and refuse (garbage) from these facilities should be sterilized or properly disposed. • EPIDEMIOLOGY Cystic echinococcosis is most prevalent in countries in the temperate zones, such as southern South America, the Mediterranean, southern and central parts of Russia, Central Asia, China, Australia, and parts of Africa. Di " Dog and cats ' Family Diphyllobothriidae Order Pseudophyllidea II. Spirometra spp. Genus Refers to the larval infection with the plerocercoid larvae, also known as spargana, of pseudophyllidean tapeworms falling under water the Genus Spirometra. • There are many species of Spirometra, but those 3 are most commonly involved in human sparganosis. • Adults of these worms are intestinal parasites of cats, dogs, and other carnivores. Primary Host: Dogs and cats First Intermediate Host: Copepod Second Intermediate Host: Fish, reptiles, and amphibians. - SPARGANOSIS • • • Spirometra mansoni Spirometra erinacei Spirometra ranarum manera HOSTS t Humans cannot serve as definitive hosts for Spirometra spp., but serve as paratenic or second intermediate hosts and develop sparganosis. 1 (DIAGNOSTIC STAGE) 2 3 4 (INFECTIVE STAGE) 5 6 PARASITE BIOLOGY LIFE CYCLE Eggs are shed in feces and embryonate in the environment. Eggs hatch in water and release coracidia. *Coracidia – larval stage of some tapeworms. The coracidia are ingested by copepods and develop into procercoid larvae in the copepod intermediate host. Second intermediate hosts, including fish, reptiles and amphibians, ingest infected copepods and acquire procercoid larvae. The procercoid larvae develop into the plerocercoid larvae in the second intermediate host. The cycle is completed when a predator (dog or cat) eats an infected second intermediate host. -7 fish etc Adult members of the genus Spirometra live in the intestines of dogs and cats. Humans cannot serve as definitive hosts for Spirometra spp., but serve as paratenic or second intermediate hosts and develop sparganosis. Spargana can live up to 20 years in the human host. Table for the Comparison of Spirometra from Diphyllobothrium Spirometra spp. Diphyllobothrium GRAVID PROGLOTTIDS Have a spiral uterus. Rosette uterus. EGGS Operculated and immature but smaller. Operculated and immature. A PATHOGENESIS AND CLINICAL MANIFESTATIONS Humans may be infected through: Drinking water containing Cyclops or copepods infected with procercoid larvae; Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes B C Eating infected second intermediate hosts like frogs, toads, or snakes containing the plerocercoid larvae; Applying plerocercoid infected flesh of frogs and snakes as poultices on sores on the eye, vagina, and skin resulting in subsequent penetration into cutaneous tissues; and D Consumption of infected flesh of paratenic hosts like wild pigs. LARVAE LOCATION LOCATION May be found in any part of the body. COMMON LOCATIONS Most commonly found in and about the eyes, subcutaneous and muscular tissues of the thorax, abdomen, thighs, inguinal region, and in the viscera. PATIENT CONDITIONS MIGRATING TUMOR Patients may complain of painful edema due to migrating larvae, hence, the condition is also known as migrating tumor. Local indurations, periodic giant urticaria, edema, and erythema with chills, fever, and high eosinophilia may be seen in patients. • • • DIAGNOSIS Sparganosis is diagnosed through the recovery of the plerocercoid larvae from infected tissues. The larvae that are opaque and glistening white usually measure about 3.5 cm in length. When the larvae are flattened, a spatulate scolex can be appreciated, together with pseudosegmentation, and a slit-like invagination at the anterior end. Species identification, however, can only be done through experimental animal infection. SURGICAL REMOVAL THE LARVAE PRAZIQUANTEL • OF TREATMENT From the infected tissues is the main form of treatment. Has been recommended, but its’ efficacy in humans has not been proven. EPIDEMIOLOGY Cases of sparganosis have been reported worldwide: in Africa, India, Holland, Australia, and South America. In Asia, the majority of cases came from Japan, Korea, Thailand, Malaysia, and Indonesia. ILLUSTRATIONS/DIAGRAMS LIFE CYCLE OF Spirometra spp. Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes Spirometra OVA Proliferating sparganum in groin tissue of a patient from Paraguay, stained with hematoxylin and eosin (H&E). Jaurigue, Lamano, Fortuno MIDTERMS | CLPARA (LEC) | MT3B Week 8 | Prof. Suratos | Extra-Intestinal Cestodes Proliferating sparganum in lung tissue in a patient from Taiwan, stained with hematoxylin and eosin (H&E). Sparganum removed from the ocular conjunctiva of a patient from Taiwan. The worm measured 40 mm long. Sparganum removed from the chest wall of a patient. The worm measured about 70 mm long. Jaurigue, Lamano, Fortuno