MLS 9 Summary Table_Nematodes PDF

MLS 9: Clinical Parasitology Lecture MODULE 2: NEMATODES 2nd Semester | S.Y. 2022-2023 LECTURER: April Dream Cisneros Catolico TRANSCRIBED BY: MLS 2B Phylum Nematoda - These are Met...

MLS 9: Clinical Parasitology Lecture MODULE 2: NEMATODES 2nd Semester | S.Y. 2022-2023 LECTURER: April Dream Cisneros Catolico TRANSCRIBED BY: MLS 2B Phylum Nematoda - These are Metazoan parasites that fall under the kingdom Animalia - Known as roundworms Elongated and cylindrical in shape with bilateral symmetry - Complete digestive tract and a muscular pharynx that is characteristically triradiate - Excretory and nervous systems are simple - They are dioecious, meaning they are provided by separate sexes. Although some are: Parthenogenetic - form of reproduction in which an egg can develop into an embryo without being fertilized by a sperm Hermaphroditic - parasites that have both male and female gonads in a single individual - Females are usually larger and the tail of males is more curled - Most are oviparous (egg laying) - Some are ovoviviparous (laying eggs with fully formed larvae) - Others are viviparous (produces larvae) Extraintestinal Nematodes Head and Tail - Size may vary from 1 mm to 10 m (L-R): W. bancrofti, B. malayi, L. loa, O. volvulus, - Amphids are nematodes with sensory organs found ANTERIORLY M. perstans, M. streptocerca, and M. ozzardi - Phasmids are nematodes with sensory organs found POSTERIORLY - Aphasmids are nematodes with NO SENSORY ORGANS such as Trichuris, Trichinella, and Capillaria - Body is covered with a noncellular cuticle, the muscles of the body wall are only one layer thick with no circular layer. - Body cavity is a pseudocele where all viscera are suspended  Intestinal Nematodes Name Common MOT Biology Life Cycle I. stage D. Stage Disease Treatment, name Laboratory D., Epidemiology, Prevention & Control Ascaris Giant Ingestion of - Lumbricoides resemblance of earthworm Ingestion of Fertilized/ Ascariasis due to TREATMENT lumbricoides intestinal embryonated - Lumbricus meaning earthworm Embryonated unfertilized ascaris infection DOC: Mebendazole roundworm eggs - One of the most common intestinal worm Eggs egg in stool & Albendazole - Superfamily: Ascaridoidea Clinical - Has a Terminal mouth manifestations can Pyrantel pamoate - Three conspicuous lips either be due to adult - 11 mg/kg once; 1 dorsal worm and migrating 1g max 2 ventrolateral larvae Albendazole Heart-lung migration - 400 mg once Asymptomatic if only Mebendazole infected with 10-20 - 100 mg BID for 3 worms days or 500 mg once Starts with vague abdominal pain Ivermectin - 150-200 mg/kg May cause: once - Vit A malabsorption - Pale pink or fresh colored - Lactose intolerance Deworming - Female produces: 240,000 eggs/day - Bowel obstruction - should have - Habitat: small intestine - Volvulus antihistamine - Pepsin Inhibitor 3 - chemical that protects - Intestinal perforation treatment with worms from digestion of gastric acid sedating effects Ascaris pneumonia - Diphenhydramine Male - Low grade fever - Smaller than female - Dry cough LABORATORY Length: 15-30 cm - Asthmatic wheezing DIAGNOSIS Thick: 2-4 cm - Urticaria DFS & Kato Posterior end is curved ventrally to form - Eosinophilia Techniques a hook and carries 2 copulatory spicules - Mottled lung - Detection of Female infiltration in the chest parasite in stool - Larger than male radiograph Serodiagnosis Length: 20-40 cm - Ascaris antibodies  Thickness: 3-6 mm Loeffler’s syndrome can be detected by: - Posterior extremity is straight and conical Blood tinged ELISA - Distinct groove at level of vulvar opening – sputum IHA vulvar waist Contain IFA Charcot-Ley Blood den crystals Examination - Biliary ascariasis - Eosinophilia may - Acute appendicitis be seen in early - Acute/Chronic stages of infection appendicitis EPIDEMIOLOGY - Globally distributed - Endemic in: SE Asia Africa Central and South America Egg - High density - Bile stained population - Fertilized - Illiteracy Laid by females inseminated by mating - Poor sanitation with male - Poor health Always bile-stained education 45-70 um - Poor hygiene Thick mammillated layer - Usage of night soil Could be decorticated as fertilized Image below is a fertilized decorticated - In the Philippines ascaris worm 27.7% of school-age children 30.9% of pre-school children - More than 1.5 billion people, 24% world’s population are infected with STH PREVENTION & CONTROL WHO  - Unfertilized - STH control Laid by inseminated female program, monitoring Can’t become infective of school-age Does not float on salt solution children 90 um WASHED Thin mammillated layer Water Composed of refractile granules Sanitation Hygiene Education Deworming War on Worms - Assisted mass drug administration - Taken over by DOH Trichuris Whipworm Ingestion of - Superfamily: Trichuroidea Embryonated Unembryonat Trichuriasis TREATMENT trichiura embryonated Closely related to Trichinella spiralis egg with L3 ed eggs in Mebendazole eggs (muscle worm) larva feces Whipworm infection - 100 mg 12 hourly - Habitat: Large intestine (cecum) for 3 to 5 days or TT47 pore Tricocefalosis 500 mg once Adult worm forming - Drug of Choice - Thin elongated anterior portion and thickened protein which No heart-lung posterior – giving a whip-like appearance allows their migration Albendazole - Male: 30-45 mm long whip-like - 400 mg once may - Female: 40-50 mm long portion to People with heavy be an alternative - Life span: 5-10 years embed in symptoms can drug - Attenuated anterior portion (contains the intestinal walls experience frequent esophagus) – embedded in the mucosa; painful passage of LABORATORY posterior part – contains intestines and stool that contains a DIAGNOSIS reproductive organs mixture of mucus, DFS or Kato water, and blood Techniques Concentration Intestinal Techniques inflammation and bleeding EPIDEMIOLOGY - 604 to 795 million Rectal Prolapse are globally infected - Children 5 to 15 years of age are  most frequently infected PREVENTION & CONTROL - similar with ascaris infection WHO - recommendation of biannual mass drug administration ​ - Lumen of appendix Egg/Ova may be irritation by - Barrel shaped/lemon shaped/football worms may lead to shaped/japanese lantern shaped inflammation and - Prominent bipolar plugs eventually - Shell is thick and composed of 3 layers: appendicitis or Outer: yellowish granuloma Inner: transparent formation - 50-55 um by 25 um - Floats on salt solution Hypochromic - female passed 3,000-2,000 eggs/day anemia are seen in chronic and massive infection but not related to blood ingestion of parasites Embed worms cause petechial hemorrhage causing ulcers susceptible for amebic dysentery Heavy infection may result in Trichuris dysentery syndrome manifested by chronic dysentery and rectal prolapse (coconut cake rectum) Result to poor appetite, wasting,  stunting as well as cognitive problems during development and learning Toxocara Ingestion of Toxocara Ingestion of L3 larvae Toxocariasis TREATMENT canis/cati eggs - Toxocara canis and cati are natural parasites of eggs migrate in - Neglected parasitic Albendazole & dogs and cats which causes aberrant infection tissues infections Mebendazole Foodborne - Aberrant infection is when the parasite cannot Foodborne - Cause: - Visceral transmission develop further in the body of the host transmission Visceral larva toxocariasis can be migrans treated by the drugs (VLM) mentioned above Ocular larva migrans LABORATORY (OLM) DIAGNOSIS Convert Tissue Biopsy toxocariasis - Definitive (CoTOX) diagnosis is based Neurological on the detection of toxocariasis larvae from tissue biopsy IgG & ELISA PCR & Medical imaging techniques PREVENTION & CONTROL - Reduced contamination of soil and environment to protect both human and animals - Control and capture of stray dogs and cats - Cleaning up feces from soil and pavements - Closing potential contaminated areas - Implementation of  strategic anti-helmintic treatment of dogs and cats Hookworm Ancylostoma Skin Two species: Filariform Rhabditiform Cause disease by TREATMENT spp. duodenale - Penetration Ancylostoma duodenale larva - larva - egg attachment to the Albendazole old world Necator americanus infective stage hatches in the human intestine, - 400 mg once for hookworm found in soil solid in 1-2 causing anemia, adults and children Ancylostoma duodenale days; protein losing over 2 years old Necator - described by Dubini in 1843, Italy undergoes 2 enteropathy - DOC both americanus - Necator americanus stages of larvicidal and new world - described by Stiles in 1902, Texas molting Stool is bloody with ovicidal hookworm - Importance was brought to attention because mucus of epidemic of miner’s anemia Eggs in Mebendazole feces Steatorrhea - 500 mg once - Habitat: small intestine (jejunum) Heart-lung migration Pyrantel pamoate - 11 mg/kg x 3 days; N. americanus: blood can be used in loss is 0.01-0.4 mL pregnancy per adu;t A. duodenale: blood Thiabendazole loss is 0.05-0.3 mL - less effective per adult Bephenium Symptoms from the hydroxynaphthoat intestinal phase of the e infection are caused - Active against by: Ancylostoma but - Necrosis of the not against Necator intestinal tissue within the adult worm LABORATORY mouth DIAGNOSIS - Blood loss by DFS direct infection of - DFS in heavy blood by the worms infections but may and continued blood not detect parasite loss from the original when eggs are attachment site