*Viruses. *Bacteria. *Fungi: Yeasts, Hyphae. Prions. Chlamidiae, Rickettsiae, Mycoplasmas. Bacteriophages, Plasmids, Transposons

Transcription

1 INFECTIOUS DISEASES

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3 Categories of INFECTIOUS AGENTS Prions *Viruses Bacteriophages, Plasmids, Transposons *Bacteria Chlamidiae, Rickettsiae, Mycoplasmas *Fungi: Yeasts, Hyphae Parasites: Protozoa, Worms, Arthropods

4 Intracellular Trichinella spiralis Trichinosis Taxonomic Classes of Human Pathogens and Their Habitats Site of Size Propagation Sample Species Disease Viruses nm Obligate intracellular Poliovirus Poliomyelitis Chlamydiae nm Obligate intracellular Chlamydia trachomatis Trachoma, urethritis Rickettsiae nm Obligate intracellular Rickettsia prowazekii Typhus fever Mycoplasmas nm Extracellular Mycoplasma pneumoniae Atypical pneumonia Bacteria µm Cutaneous Staphylococcus aureus Wound Mucosal Vibrio cholerae Cholera Extracellular Streptococcus pneumoniae Pneumonia Facultative intracellular Mycobacterium tuberculosis Tuberculosis Fungi µm Cutaneous Trichophyton sp. Tinea pedis (athlete's foot) Mucosal Candida albicans Thrush Extracellular Sporothrix schenckii Sporotrichosis Facultative intracellular Histoplasma capsulatum Histoplasmosis Protozoa 1 50 µm Mucosal Giardia lamblia Giardiasis Extracellular Trypanosoma gambiense Sleeping sickness Facultative intracellular Trypanosoma cruzi Chagas disease Obligate intracellular Leishmania donovani Kala-azar Helminths 3 mm 10 m Mucosal Enterobius vermicularis Enterobiasis Extracellular Wuchereria bancrofti Filariasis

5 PRIONS, BSE (Cows), CJD, Kuru (Humans) NON-Nucleic Acid PrP = Prion Protein Diagnostic Test

6 Bovine Spongiform Encephalitis, Creutsfeldt-Jakob Disease

7 VIRUSES Less than ½ micron, usually MUCH less DNA/RNA CORE (genome) Protein CAPSID (protein NA coat ) Sometimes a lipid ENVELOPE Limited number of genes coding for all other structures NO consistent naming system

8 Respiratory Adenovirus Adenoviridae DS DNA Upper and lower respiratory tract infections, conjunctivitis, diarrhea Rhinovirus Picornaviridae SS RNA Upper respiratory tract infection Coxsackievirus Picornaviridae SS RNA Pleurodynia, herpangina, handfoot-and-mouth disease, SARS Coronavirus Coronaviridae SS RNA Upper respiratory tract infection Influenza viruses A, B Orthomyxoviridae SS RNA Influenza Respiratory syncytial virus Paramyxoviridae SS RNA Bronchiolitis, pneumonia

9 Digestive Mumps virus Paramyxoviridae SS RNA Mumps, pancreatitis, orchitis Rotavirus Reoviridae DS RNA Childhood diarrhea Norwalk agent Caliciviridae SS RNA Gastroenteritis Hepatitis A virus Picornaviridae SS RNA Acute viral hepatitis Hepatitis B virus Hepadnaviridae DS DNA Acute or chronic hepatitis Hepatitis D virus Viroid-like SS RNA With HBV, acute or chronic hepatitis Hepatitis C virus Flaviviridae SS RNA Acute or chronic hepatitis Hepatitis E virus Norwalk-like SS RNA Enterically transmitted hepatitis

10 Systemic with Skin Eruptions Measles virus Paramyxoviridae SS RNA Measles (rubeola) Rubella virus Togaviridae SS RNA Parvovirus Parvoviridae SS DNA Vaccinia virus Poxviridae DS DNA Varicella-zoster virus Herpesviridae DS DNA German measles (rubella) Erythema infectiosum, aplastic anemia Smallpox vaccine Chickenpox, shingles Herpes simplex virus 1 Herpesviridae Herpes simplex virus 2 Herpesviridae DS DNA DS DNA "Cold sore" Genital herpes

11 Systemic with Hematopoietic Disorders Cytomegalovirus Herpesviridae DS DNA Cytomegalic inclusion disease Epstein-Barr virus Herpesviridae DS DNA Infectious mononucleosis HTLV-I Retroviridae SS RNA Adult T-cell leukemia; tropical spastic paraparesis HIV-1 and HIV-2 Retroviridae SS RNA AIDS Dengue virus 1 4 Arboviral and Hemorrhagic Fevers Togaviridae SS RNA Dengue, hemorrhagic fever Yellow fever virus Togaviridae SS RNA Yellow fever Regional hemorrhagic fever viruses Filoviridae Hantavirus SS RNA Ebola, disease SS RNA Korean, pneumonia

12 Warty Growths Papillomavirus Papovaviridae DS DNA Condyloma; cervical carcinoma Central Nervous System Poliovirus Picornaviridae SS RNA Poliomyelitis JC virus Papovaviridae DS DNA Progressive Multifocal Leukoencephalopathy (opportunistic) Arboviral encephalitis viruses Togaviridae SS RNA Eastern, Western, Venezuelan, St. Louis

13 BACTERIOPHAGES PLASMIDS TRANSPOSONS INFECT BACTERIA, but may make a bacteria more difficult to treat because it may increase its virulence or its susceptibility to antibiotics

14 BACTERIA GRAM staining with CRYSTAL VIOLET POSITIVE: THICK wall, ONE phospholipid layer NEGATIVE: THIN wall, TWO phospholipid layers SHAPE COCCI (balls) BACILLI (rods) OXYGEN requirements AEROBIC (NEED O2) ANAEROBIC (do NOT NEED O2)

15 Species Frequent Disease Presentations Infections by pyogenic cocci Staphylococcus aureus, S. epidermidis Streptococcus pyogenes, β- hemolytic Abscess, cellulitis, pneumonia, septicemia Upper respiratory tract infection, erysipelas, scarlet fever, septicemia Gram-negative infections, common Streptococcus pneumoniae (pneumoccoccus) Neisseria meningitidis (meningococcus) Neisseria gonorrhoeae (gonococcus) Lobar pneumonia, meningitis Cerebrospinal meningitis Gonorrhea * Escherichia coli Urinary tract infection, wound infection, abscess, pneumonia, septicemia, endotoxemia, endocarditis * Klebsiella pneumoniae * Enterobacter (Aerobacter) aerogenes * Proteus spp. (P. mirabilis, P. morgagni) * Serratia marcescens * Pseudomonas spp. (P. aeruginosa) Bacteroides spp. (B. fragilis) Anaerobic infection Legionella spp. (L. pneumophila) Legionnaires disease

16 Contagious childhood bacterial diseases Haemophilus influenzae Meningitis, upper and lower respiratory tract infections Enteropathic infections Bordetella pertussis Corynebacterium diphtheriae Enteropathogenic E. coli Shigella spp. Vibrio cholerae Campylobacter fetus, C. jejuni Yersinia enterocolitica Salmonella spp. (1000 strains) Whooping cough Diphtheria Invasive or noninvasive gastroenterocolitis, some with septicemia Clostridial infections Salmonella typhi Typhoid fever Clostridium tetani Tetanus (lockjaw) Clostridium botulinum Botulism (paralytic food poisoning) Clostridium perfringens, C. septicum Gas gangrene, necrotizing cellulitis * Clostridium difficile Pseudomembranous colitis

17 Zoonotic bacterial infections Bacillus anthracis Anthrax (malignant pustule) * Listeria monocytogenes Listeria meningitis, listeriosis Yersinia pestis Francisella tularensis Bubonic plague Tularemia Brucella melitensis, B. suis, B. abortus Burkholderia mallei, B. pseudomallei Leptospira spp. (many groups) Borrelia recurrentis Borrelia burgdorferi Bartonella henselae Spirillum minus, Streptobacillus moniliformis Brucellosis (undulant fever) Glanders, melioidosis Leptospirosis, Weil disease Relapsing fever Lyme borreliosis Cat-scratch disease; bacillary angiomatosis Rat-bite fever

18 Human treponemal infections Treponema pallidum Treponema pertenue Treponema carateum (T. herrejoni) Venereal, endemic syphilis (bejel) Yaws (frambesia) Pinta (carate, mal pinto) Mycobacterial infections *Mycobacterium tuberculosis, M. bovis (Koch bacillus) M. leprae (Hansen bacillus) *M. kansasii, M. avium, M. intracellulare Tuberculosis Leprosy Atypical mycobacterial infections M. ulcerans Buruli ulcer Actinomycetaceae Nocardia asteroides * Nocardiosis Actinomyces israelii Actinomycosis

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20 Chlamydiae Rickettsiae Mycoplasmas Like Bacteria, but.. NO cell wall (mycoplasma [MANY pneumonias]) NO ATP (chlamydia [STD, worldwide blindness]) NO life outside a cell (obligate intracellular, rickettsiae [RMSF])

21 YEASTS, HYPHAE FUNGI CANDIDA, by far, the MOST PREVALENT ONE DERMATOPHYTES, ( tinea ), i.e., epidermophyton, trichophyton, microsporum DEEP FUNGI (GRANULOMAS) HISTOPLASMOSIS BLASTOMYCOSIS COCCIDIOMYCOSIS

22 YEASTS, HYPHAE

23 PARASITES PROTOZOA META -ZOA (HELMINTHS) ECTO -PARASITES, i.e., ARTHROPODS

24 PROTOZOA PLASMODIUM (MALARIA) LEISHMANIA ENTAMOEBA TRYPANOSOMA TOXOPLASMA GIARDIA SINGLE CELL INTESTINAL or BLOOD

25 Species Order Form, Size Disease Luminal or Epithelial Entamoeba histolytica Amebae Trophozoite µm Amebic dysentery; liver abscess Balantidium coli Ciliates Trophozoite µm Colitis Naegleria fowleri Ameboflagellates Trophozoite µm Meningoencephalitis Acanthamoeba sp. Ameboflagellates Trophozoite µm Meningoencephalitis or ophthalmitis Giardia lamblia Mastigophora Trophozoite µm Diarrheal disease, malabsorption Isospora belli Coccidia Oocyst µm Chronic enterocolitis or malabsorption or both Cryptosporidium sp. Coccidia Oocyst 5 6 µm Trichomonas vaginalis Mastigophora Trophozoite µm Urethritis, vaginitis Bloodstream Plasmodium species Hemosporidia Trophozoites, schizonts, Malaria gametes (all small and inside red cells) Babesia microti, B. bovis Hemosporidia Trophozoites inside red cells Babesiosis Trypanosoma species Hemoflagellates Trypomastigote µm African sleeping sickness Intracellular Trypanosoma cruzi Hemoflagellates Trypomastigote 20 µm Chagas disease Leishmania donovani Hemoflagellates Amastigote 2 µm Kala-azar Leishmania species Hemoflagellates Amastigote 2 µm Cutaneous and mucocutaneous leishmaniasis Toxoplasma gondii Coccidia Tachyzoite 4 6 µm (cyst larger) Toxoplasmosis

26 HELMINTHS (ROUND[nematode]), TAPE[cestode]) Roundworms, Tapeworms Complex Life Cycles: sexual, asexual ROUNDWORMS (nematodes): ASCARIS, TOXOCARA (VLM), STRONGYLOIDES, ENTEROBIUS TAPE(FLAT)WORMS (cestodes): TAENIA (solium vs. saginata), DIPHYLLOBOTHRIUM, Hymenolepsis

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28 Ascaris life cycle

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31 ARTHROPODS: INSECTS/ARACHNIDS LICE BEDBUGS FLEAS MITES TICKS SPIDERS

32 CLASS INSECTA C R A B L O U S E L O U S E BEDBUG FLEA

33 CLASS ARACHNIDA TICK LARVAL MITE ADULT MITE BLACK WIDOW BROWN <--RECLUSE

34 S C A B I E S

35 BARRIERS ALL ANATOMIC MUCOSAL POSSIBILITIES SKIN GI RESPIRATORY UROGENITAL

36 SAME AS TUMOR? DIRECT EXTENSION LYMPHATICS BLOOD NERVE

37 RELEASE (TRANSMISSION) SKIN SHEDDING COUGHING/SNEEZING URINE FECES BLOOD VECTORS, e.g., insects, zoonosis STDs (Sexually Transmitted Diseases)

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39 INFECTIVITY, GENERAL AGENT HOST CELL AGENT TOXINS NECROSIS AGENT HOST CELLULAR REACTION DAMAGE/DEATH

40 INFECTIVITY, VIRAL ATTACHMENT ENTRY TRANSCRIPTION TRANSLATION INCLUSIONS REDUCED HOST CELL FUNCTION CELL INJURY, LYSIS, DEATH LATENCY NEOPLASM?

41 INFECTIVITY, BACTERIAL ADHERENCE ENTRY TOXINS ENDO, Gram -, bacterial components EXO, Gram -/+, secreted proteins

42 IMMUNE EVASION INACCESSIBILITY to host defense (Mr. Myagi) VARYING (mutating) antigens SHEDDING antigens RESISTING INNATE (NATURAL) immunity IMPAIRING T-CELLS

43 INFECTIONS of IMMUNOSUPPRESSED HOSTS Protozoal/Helminthic: Cryptosporidium, PCP (Pneumocystis Carinii Pneumonia), Toxoplasmosis Fungal: Candida, and the usual 3 Bacterial: TB, Nocardia, Salmonella Viral: CMV, HSV, VZ

44 DIAGNOSTIC TECHNIQUES DIRECT PATHOGEN IMAGING GRAM STAIN SPECIAL (NOT H&E) STAINS AGAR, e.g., CULTURES TISSUE CULTURE, CPE (CytoPathological Effect) ANTIBODIES (SEROLOGY) PCR, POLYMERASE CHAIN REACTION, e.g., viral LOAD

45 CELLULAR HOST RESPONSES SUPPURATIVE (NEUTROPHILS, PMNs) (cultures may be positive) MONO-NUCLEAR, i.e., Lymphocytes, Macrophages (i.e., Monocytes), GRANULOMAS FIBROSIS HEMOSIDERIN CALCIFICATION

46 ACUTE APPENDICITIS

47 ABSCESS

48 CHRONIC MONONUCLEAR INFLAMMATION

49 GRANULOMA

50 FIBROSIS

51 H H & E E M O S I D E R I N PRUSSIAN BLUE

52 Calcification

53 The 4 Biggies VIRAL BACTERIAL FUNGAL PARASITIC

54 TRANSIENT, ACUTE, e.g. Measles, Mumps, Polio, West Nile CHRONIC LATENT (HERPES FAMILY), HSV, CMV, VZ CHRONIC (HEPATITIS), Hep A, B, C TRANSFORMING (Epstein-Barr EBV, Human Papilloma, HPV)

55 BACTERIAL Gram+ Gram- MYCO-bacteria SPIROCHETES ANAEROBIC OBLIGATE INTRACELLULAR

56 FUNGAL YEASTS CANDIDA CRYPTOCOCCOSIS MOLDS (HYPHAL) ASPERGILLIS MUCORMYCOSIS (ZYGOMYCOSIS)

57 PARASITES PROTOZOA (GI, BLOOD) METAZOA (WORMS)

58 TRANSIENT, ACUTE Measles: Skin, Lung, GI, Cornea, Brain Mumps: Parotitis, Orchitis, Pancreas, CNS Polio: Myelitis (Anterior horn motor neurons) West Nile (arbo-): Meningoencephalitis

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63 CHRONIC LATENT (HERPES FAMILY), HSV, CMV, VZ Herpes Simplex Virus CytoMegalo Virus Varicella-Zoster Virus

64 HSV

65 CONGENITAL IMMUNOSUPPRESSED BASOPHILIC CMV pneumonia

66 VZ Virus

67 CHRONIC (HEPATITIS), Hep. A, B, C A, Mildest, most universal B, Most dangerous in the acute phase, but most are SUB-clinical C, Most common cause of persistent transaminitis

68 NORMAL LIVER

69 ACUTE VIRAL HEPATITIS

70 TRANSFORMING Epstein-Barr, EBV, lymphoma Human Papilloma, HPV, cervical cancer (squamous cell)

71 PHARYNX NODES SPLEEN LIVER HETEROPHILE MONONUCLEOSIS, caused by EBV

72 MALIGNANT cells on PAP smear, caused by HPV

73 BACTERIAL Gram+ (Staph, Strep) Gram- (rods) MYCO-bacteria (TB) SPIROCHETES (SYPHILIS) ANAEROBIC (ABSCESSES) OBLIGATE INTRACELLULAR

74 BACTERIAL Gram+ cocci (Staph, Strep) SKIN RESPIRATORY TRACT

75 S T A P H

76 STREP: SKIN RESPIRATORY ERISIPELAS

77 GRAM POSITIVE RODS DIPTHERIA LISTERIA ANTHRAX NOCARDIA CLOSTRIDIUM

78 GRAM NEGATIVE COCCI Neisseria GONORRHEA MENINGITIS

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80 GRAM NEGATIVE RODS Bordetella pertussis Pseudomonas aeruginosa Klebsiela/Aerobacter Yersinia pestis (plague) Hemophilus ducreyi (chancroid) E. COLI

81 MYCOBACTERIA (acid fast) Tuberculosis Atypical mycobacteria, the most important of which is MAC (Mycobacterium Avium Intercellulare Complex, in HIV patients) Leprosy

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83 MORE ACID-FAST BACILLI, AFB (MAC)

84 SPIROCHETES SYPHILIS (Treponema pallidum) RELAPSING FEVER (Borrelia sp.) LYME DISEASE (Borrelia burgdorferi)

85 PRIMARY (CHANCRE) SECONDARY (MANY skin manifestations) TERTIARY (GUMMAS, CNS, BONE) CONGENITAL

86 ANAEROBES Clostridium (Gram + bacillus) Cause of many/most cases of gas gangrene

87 OBLIGATE intracellular bacteria Chlamydia trachomatis Conjunctivitis LGV (LymphoGranuloma Venerium) Urethritis Rickettsia (Rocky Mountain Spotted Fever, Typhus) Mycoplasma (very common cause of pneumonias)

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89 RMSF

90 FUNGAL YEASTS CANDIDA CRYPTOCOCCOSIS MOLDS (HYPHAL) ASPERGILLIS MUCORMYCOSIS (ZYGOMYCOSIS)

91 Candida albicans Oral Vaginal Esophageal All of the above are moist nonkeratinized squamous mucosa Immunocompromised, e.g., HIV, Diabetes

92 Budding Yeasts and PSEUDO hyphae

93 Budding cryptococcal yeasts, India ink prep, CSF

94 Aspergillus Zygomycosis (Mucormycosis)

95 DERMATOPHYTES ( TINEAS ) (superficial fungi) EPIDERMOPHYTON MICROSPORUM TRICHOPHYTON

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102 SIGNIFICANT FUNGI (deep) HISTOPLASMOSIS BLASTOMYCOSIS COCCIDIOMYCOSIS

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104 PROTOZOA MALARIA (Plasmodium sp., of which falciparum is the most serius) Babesiosis, transmitted by deer tick Leishmaniasis Trypanosomiasis (sleeping sickness) Chagas disease (also a trypanosome) Entamoeba histolytica

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108 GAMETOCYTES Are COMMON And SAUSAGE shaped

109 S C H U F F N E R S D O T S

110 Affected RBC s are NOT enlarged NO SCHUFFNER s DOTS

111 S C H U F F N E R S D O T S comets

112 TRYPANOSOMIASIS

113 METAZOA (ROUNDworms/FLATworms) Strongyloides (microscopic roundworm) Tapeworms (Beef, Pork, flatworm) Trichinosis (larva in skeletal muscle) Schistosomiasis (bladder cancer) Filariasis (elephantiasis) VERY OFTEN, COMPLEX LIFE CYCLES

114 Ascaris life cycle

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