Microbiology Q4
Tonsils
-5 tonsils: 2 lingual 2 palatine 1 adenoid -contain many T and B cells -capture pathogens that may enter through the respiratory system
Granular Leukocytes:
-Eosinophils=reduce allergic inflammation and help fight parasites -Basophils=trigger inflammation -Neutrophils=act as first responders to the site of infection
Viscerotropic Viruses:
-Hep A -Hep B -Hep C -Epstein-Barr virus -Cytomegalovirus -Mumps
Lymphoma
-Hodgkin's lymphoma: giant cells (Reed-Sternberg cells) -Non-Hodgkin's lymphoma: no Reed-Sternberg cells
Lymphoid Stem Cells:
-T lymphocytes (T-cells) -Helper T-cells -Memory T-cells -B lymphocytes (B-cells) -Antibodies -Memory B-cells
Dermatropic Viruses: Varicella Zoster Virus (aka chicken pox)
-a herpes virus (reactivation potential) -mode of transmission: droplet -portal of entry/exit: respiratory tract -causes skin lesions/rashes -seroius complication generally associated with younger children is *Reye's syndrome* which causes severe brain swelling that can lead to coma, permanent brain damage, or death -effective vaccine available
Lymphedema
-abnormal fluid accumulation due to inadequate lymph drainage -often follow surgery which requires removal of lymph nodes
Tonsilitis
-acute inflammation of the tonsils -painful sore throat, enlarged tonsils and adenoids, red and spotted swollen tonsils -painful swallowing -contagious and communicable
Viscerotropic Viruses: Hepatitis B Virus (HBV) *serum hepatitis*
-acute inflammatory disease of the liver -mode of transmission: contact with infected body fluids, intravenous or sexual -portal of entry/exit: broken skin or mucous membranes -long term liver damage or increased liver cancer risk
Viscerotropic Viruses: Hepatitis A Virus (HAV) *infectious hepatitis*
-acute inflammatory disease of the liver -mode of transmission: ingestion -portal of entry/exit: GI tract -vaccine available
Histoplasma capsulatum (Histoplasmosis)
-aka Darling's disease; Cave sickness -soil fungus endemic to Mississippi and Ohio River Valley regions -found in bat and bird feces; acquired by inhalation of contaminated particles -mild self-limiting respiratory illness in healthy people; more serious systemic infections in others
Coccidiodes immitis (Coccidomycosis)
-aka Valley Fever; Desert Rheumatism -soil fungus endemic to arid regions -humans acquire by inhalation -mild self-limiting respiratory illness in healthy people; more serious systemic infections in others
Lymphatic ducts
-all lymph vessels drain into 2 lymphatic ducts: *thoracic or right lymphatic duct*
Right Lymphatic duct
-all lymphatic vessels of the arm, right side of the head, and thorax drain into the right lymphatic duct which empties into the *right brachiocephalic vein*
Thoracic duct
-all lymphatic vessels of the legs, abdomen, left arm, and left side of head, neck and thorax drain into the thoracic duct which empties the filtered lymph into the *left brachiocephalic vein*
Monocytes:
-are granular leukocytes -macrophages=phagocyte -dendritic cells=found on skin and mucous membranes (detect pathogenic antigens which activate T and B cells)
Cryptococcus neoformans (Cryptococcosis)
-birds carry fungus on their feet and beaks; disseminate spores in their feces; humans acquire by inhalation of spores -healthy individuals get mild respiratory illness; others - more serious systemic infections
Immune Cell Generation
-bone cells are produced in red bone marrow -all leukocytes (WBCs) of the immune system are produced by red bone marrow
Candidia Albicans:
-causative agent of superficial yeast infections or candidiasis (thrush, vaginitis) -common in HIV patients
Toxoplasma gondii
-causative agent of toxoplasmosis -found in feces of cats that forage for rodents -primary concern is the ability of this organism to cross the placenta and cause miscarriage or still birth -causes encephalitis in AIDS patients
Pneumotropic Viruses: Rhinoviruses and Coronoviruses
-cause the common cold -portal of entry/exit: respiratory tract -mode of transmission: droplet -vaccines not very helpful; 200+ strains of virus cause the common cold
Pneumotropic Viruses: Hantavirus
-causes Hantavirus Pulmonary Syndrome (HPS) -aka four-corners disease -hemorrhaging, lung infection, and kidney problems -mode of transmission: inhalation -portal of entry/exit: respiratory tract
Neurotropic Viruses: Poliovirus
-causes poliomyelitis or polio -gray matter of nervous tissue of brain and spinal cord is affected -port of entry/exit: GI tract -mode of transmission: ingestion -2 vaccines: ---Salk: inactivated vaccine, injected ---Sabin: attenuated vaccine, oral
Neurotropic Viruses: Arbovirus
-causes types of arboviral encephalitis -arthropodborne; mosquito, biological vector -portal of entry/exit: broken skin -mode of transmission: bite of infected mosquito -examples: West Nile, Western Equine, La Crosse, Japanese B, St. Louis, California encephalitis
Immunological Viruses: Human Immunodeficiency Virus (HIV) *can progress to clinical AIDS*
-considered a global pandemic -primarily affect drug users, homosexual, and bisexual males in developed countries although heterosexual spread is increasing rapidly -3rd world countries transmission is almost entirely from heterosexual contacts; more than 25% of total population is infected in parts of Africa -rapid mutation of HIC makes a vaccine difficult to create; HIV spreads in several ways -Chemotherapy and drug treatments have become more advanced but no cure exists; the medications only slow the virus down
Plasmodium malariae (P. falciparum, P. vivax, P. ovale)
-contaminated agent of malaria -humans acquire by the bite of infected female mosquito (anopheles)
Viscerotropic Viruses: Mumps Virus (aka *epidemic parotitis or mumps*)
-enlarged jaw tissues from swollen salivary glands, especially the parotids -transmission via contact with infected saliva or respiratory fluids -MMR vaccine
Lymphadenopathy
-enlargement of the lymph nodes -caused by infectious agents, cancer, autoimmune disease, adverse drug reactions
Splenomegaly
-enlargement of the spleen -common causes are viral, parasitic or bacterial infection, cirrhosis (liver), inflammation of the gall bladder (cholecystitis), cystic fibrosis, anemia, leukemia, lymphoma, and sickle cell anemia
Microsporum, Trichophyton, Epidermophyton:
-fungal infections of the hair, skin and nails -superficial fungal infections, cutaneous mycoses, dermatomycoses -tinea or ringworm infections
3 forms of CJD:
-genetic: 10-15% of cases -sporadic: unknown cause, 80-85% of cases -iatrogenic/infectious: from contamination with dura mater grafts or corneal implants from person to person; 5% or less
Dermatropic Viruses: Herpes Simplex Virus Type 2
-genital lesions -transmitted by sexual contact, placental transmission, or the birth canal
Viscerotropic Viruses: -Hepatitis C Virus (HCV) *non-A, non-B hepatitis*
-inflammatory disease of the liver -long term liver damage, increased liver cancer risk -mode of transmission: contact with infected body fluid -portal of entry/exit: broken skin or mucous membranes
Lymphangitis
-inflammatory disorder of lymph vessels -usually in associated with a bacterial infection of the skin -red streaks in area of infection, throbbing pain in the area, fever, chills, anorexia, headache, and muscle aches
Pneumotropic Viruses:
-influenza -rhinovirus and coronaviruses -hantavirus -SARS
Lymph
-interstitial fluid -absorbed by lymph capillaries so that too much extra cellular fluid does not accumulate -EDEMA -mostly water (90%) 10% dissolved or suspended -dead cells, cancer cells, WBC also be may present
Peyer's Patches
-located in the villi of the small intestine (ileum) -contain T and B cells -protect against pathogens in the lumen of the intestine
Anatomy of Lymph System
-lymph capillaries, lymph, lymphatic vessels, lymph nodes, lymphatic ducts, tonsils, adenoids, spleen, Peyer's patches, and thymus
Lymphatic Vessels
-lymphatic capillaries merge into larger lymphatic vessels and the lymph is returned to circulation -lymphatic vessels closely resemble veins in that they are thin-walled with many "check-valves" -lymph moves through the lymphatic circulation b/c of skeletal muscle contraction
Dermatropic Viruses: German Measles virus (aka Rubella virus/3 day measles)
-mode of transmission: droplet -portal of entry/exit: respiratory tract -cause skin lesions/rashes -crosses the placenta (congenital rubella), neurological complications -effective vaccine: MMR
Dermatropic Viruses: Measles Virus (aka Rubeola virus)
-mode of transmission: droplet -portal of entry/exit: respiratory tract -extremely contagious -causes skin lesions/rashes -lesions of the oral cavity are known as Koplik's spots -effective vaccine: MMR
Dermatropic Viruses: Smallpox virus (aka Variola virus)
-most common mode of transmission: droplet -most common portal of entry/exit: respiratory tract -causes skin lesions/rashes which can lead to scarring and pitting -effective vaccination has led to worldwide eradication
Viscerotropic Viruses: Cytomegalovirus (CMV) *CMV Inclusion Disease*
-named for the enlarged cells found in infected tissues -most cases are asymptomatic -crosses the placenta causing neurological damage to the fetus -virus is found in most bodily fluids, many modes of transmission
Pneumocystis jirovecii (carinii) (Pneumocystis pneumonia (PCP))
-opportunistic organism -found in flora of healthy human lungs in very low levels or completely absent -fairly common in larger amounts in the lungs of seriously immune-compromised people -common infection in AIDS patients
Dermatropic Viruses: Herpes Simplex Virus Type 1
-oral lesions, cold sores, or fever blisters -transmitted by some type of direct contact with infected lesions, saliva, or mucous membranes
Entamoeba histolytica (Amoebic dysentery) (amoebiasis)
-pathogenic protozoan amoeba; cysts found in contaminated feces -humans acquire by ingestion of contaminated food or water
Pneumotropic Viruses: Influenza
-portal of entry/exit: respiratory tract -mode of transmission: droplet -vaccines available; but many different strains
Creutzfeldt-Jakob Disease:
-prion disease -infectious, progressive, degenerative neurological disease -extremely hardy, can survive in a dried state for years, very resistant to chemical disinfectants and sterilants -always fatal* -aka transmissible spongiform encephalopathy
Thymus
-produces and trains T-cells during development and childhood -at puberty the role of the thymus is diminished b/c the immune system is mature
Neurotropic Viruses: Rhabdovirus
-rabies -portal of entry: broken skin -mode of transmission: biological vector, bit of infected animal -causes brain degeneration, inability to swallow, hydrophobia
Dermatropic Viruses: Herpes Zoster Virus (aka Shingles virus)
-reactivation of the dormant Varicella zoster virus
Neurotropic Viruses:
-rhabdovirus -poliovirus -arbovirus
Pneumotropic Viruses: SARS
-severe acute respiratory syndrome -fever, headache, body aches, dry cough, respiratory problems -mode of transmission: droplet, contact -rare
Lymph nodes
-small oval organs; several hundred in the body (600-700) -mostly in thorax and abdomen -contain many lymphocytes and macrophages -function as filters -most are found in axillary and inguinal (groin) area
Dermatropic Viruses:
-smallpox -measles -german measles -varicella zoster -herpes zoster -herpes simplex virus type 1 -herpes simplex virus type 2
Viscerotropic Viruses: Epstein-Barr Virus (EBV) *infectious mononucleosis, mono; kissing disease (herpes virus)*
-spread by contact with infected saliva -usually those infected become carriers for months -has also been detected in patients who have Burkitt's lymphoma, a tumor of the connective tissues of the jaw (Africa and Asia)
Macroscopic parasites:
-tapeworms -roundworms -flukes
Lymph Capillaries
-tiny vessels that absorb interstitial fluid (b/n cells) that has left the circulatory system -fluids are eventually returned to circulation after filtration
Lymphatic nodules
-tonsils, adenoids (pharyngeal area) -Peyer's Patches (small intestine) -spleen (largest of lymph nodules) -upper left quadrant of abdominal area lateral to stomach -thymus posterior to sternum and anterior to heart
Spleen
-where RBC are destroyed after being removed from circulation (Red Pulp Area) -T cells, B cells, and macrophages are stored in the White Pulp Area of spleen to fight off infections
Aspergillus fumigatus (Aspergillosis)
-widespread in decaying vegetation; compost piles, manure, soil -humans acquire by inhalation of airborne particles -pneumonia and granular tumors in the lungs and possibly disseminating to other organs of the body
Cytomegalovirus =
CMV Inclusion Disease
Hantavirus =
Hantavirus Pulmonary Syndrome (HPS)
Immunological Viruses:
Human Immunodeficiency Virus (HIV) *can progress to clinical AIDS*
SARS =
Severe Acute Respiratory Syndrome
Arbovirus =
arboviral encephalitis
Varicella Zoster =
chicken pox
Rhinoviruses and Coronoviruses =
common cold
Mumps =
epidemic parotitis or mumps
B lymphocytes or B-cells
fight specific pathogens -once activated, B-cells form plasma cells which produce antibodies
T lymphocytes or T-cells
fight specific pathogens in body
Trematodes=
flukes
Helper T-cells
help other immune cells
Hepatitis A =
infectious hepatitis
Epstein-Barr =
infectious mononucleosis, mono; kissing disease (herpes virus)
Antibodies
neutralize pathogens until they can be destroyed by other immune cells
Hepatitis C =
non-A, non-B hepatitis
Poliovirus =
poliomyelitis or polio
Myeloid Stem Cells
produce monocytes and granulocytes (eosinophils, basophils, and neutrophils)
Rhabdovirus =
rabies
Memory T-cells
remain in body for a rapid response to the same pathogen (antigen)
Memory B-cells
remain in body for quick response to same pathogen
Nematodes=
roundworms
German Measles =
rubella / 3 day measles
Measles =
rubeola
Hepatitis B =
serum hepatitis
Herpes Zoster =
shingles
Cestodes=
tapeworms
Smallpox =
variola
Immune system:
works closely with the lymphatic system to protect and defend against infections and disease (cancer)
