PASS Parasites.pdf

Chapter Thirty-Five: Parasites and Protozoa Liver Flukes Attack the liver Patients will have elevated liver enzymes & elevated bilirubin All of these organisms cause gastroenteritis Schistosomiasis Squamous cell bladder cancer Echinococcus Dog, lamb meat. Hydatid cyst Toxocara (canis or cati) Cutane...

Chapter Thirty-Five: Parasites and Protozoa Liver Flukes Attack the liver Patients will have elevated liver enzymes & elevated bilirubin All of these organisms cause gastroenteritis Schistosomiasis Squamous cell bladder cancer Echinococcus Dog, lamb meat. Hydatid cyst Toxocara (canis or cati) Cutaneous larva migrans Clonorchis/Opisthorchis (sinensis) more common in asia. lives in billiary tract. Tx: Praziquantel Hookworms Hook into the bowel wall using their microtubules Diarrhea is more severe Necator Americanus Most common Enterobius Vermicularis Pin worms, pruritus ani, lives in the caecum, lays eggs at night Ascaris Lumbricoides sensitive olfactory and can leave body when food is around Trichuris Trichiura Tenesmus, constipation Ancylostoma Duodenale Strongyloides penetrates the feet Tx: Mebendazole; Albendazole; Thiabendazole; Pyrantel Pamoate Strongyloides Flatworms Taenia saginata Raw beef Taenia solium Raw pork Diphyllobothrium latum Megaloblastic anemia - B12 eaten Trichinella spiralis Bear meat Tx: Niclosamide/Hyclosamine Protozoa Eukaryotes CNS o Trypanosoma Rhodiensis african sleeping sickness, tsetse fly o Toxoplasma Gondii (Ring enhancing lesions seen in the brain) Raw pork, stagnant water o Naegleria Fowleri Premethamine and Sulfadrazine Cornea or o Ehrlichiosis ixodes tick, east coast, Puromycin for Pregnant o Acanthamoeba Lymphatics o Wuchereria Bancrofti (causing Elephantiasis) Blocks lymphatic drainage Pulmonary o Pneumocystis Jirovecii CD 4 < 200 in HIV, silver stains in the lungs, if hypoxic add steroids Cardiac o Trypanosoma Cruzi south america, reduvid “kissing” bug, eats ganglia 847 Parasites and Protozoa GI o Giardia Lamblia pear shaped, with flagella, metronidazole o Entamoeba histolytica Multiple liver abscesses, traveling, o Cryptosporidium Secretory diarrhea, water based, only partial acid fast protozoa, cirpofloxacin o Cystoisospora belli, formerly known as Isospora Belli Genitourinary o Trichomonas Vaginalis frothy green, metronidazole (treat partner) Skin Donovani- ulcers on the face. sand flies o Leishmania (Rhodiensis) Rhodiensis- ulcersn on internal organs Blood o Babesiosis Malaria like but never traveled, Ixodes Tick o Plasmodium Most common infectious disease in the world and most common deaths P. malariae Most common strain. Fever every 3rd day. P. falciparum Most fatal P. vivax Attacks only reticulocytes P. ovale o Tx: chloroquine Carribean, weak mosquitoes Produce reactive oxygen species and cause Quinine hemolysis to increase new rbc formation. Mefloquine Standard for travel can cause cinchonism Primaquine Best liver penetration (Ovale) colorful dreams Tetracyclines burning skin Malaria The most common infectious disease in the world The most common cause of infectious disease-related deaths in the world The most common cause of hemolytic anemia in the world 848 Chapter Thirty-Six: Mycobacterium, Spirochetes and Rickettsia Mycobacterium Not a true bacterium Has bacterium in its name because it has a peptidoglycan wall Atypical due to mycolic acid in its membrane Causes a Cell mediated inflammatory response If you destroy mycolic acid, you destroy mycobacterium Mycolic Acid A special lipid found in the wall of mycobacterium INH works by inhibiting mycolic acid synthesis It is the most effective drug against Tuberculosis Isoniazid (INH) Inhibits the synthesis of mycolic acid Fat soluble Pulls vitamin B6 out of the body Must give vitamin B6 with this drug to prevent neuropathy Side effects: myositis; hepatitis; hepatic necrosis (especially after age 35 years); neuropathy; oxidizes RBCs: blocks P450 (mnemonic: Injures Nerves & Hepatocytes) Primary response to Mycobacterium Asymptomatic Ghon focus: naked tubercle on respiratory epithelium Virulence factor: chord factor Ghon complex: tubercle ingested by macrophages and taken to the perihilar lymph nodes Granuloma: macrophages now surrounded by T-helper cells Primary Tuberculosis Usually lands in the right lower lobe in the terminal bronchioles Once Granuloma is formed: three new cytokines are made: Interferon: interferes with protein synthesis and mediates macrophage transformations Tumor Necrosis Factor: increases basal metabolic rate; responsible for weight loss: high concentrations cause endotoxemia 1-hydroxylase: activates vitamin D. Responsible for hypercalcemia in granulomatous diseases Infliximab An antibody against TNF Useful in patients with RA Decreases joint destruction As long as your T cells and macrophages stay healthy, you have nothing to worry about. 849