final microbiology

Fecal/oral route

The typical route of transmission for microbial diseases of the digestive system.

Dental Plaque

A biofilm on the surface of teeth where organisms ferment carbohydrates, creating lactic acid.

Lactic acid

Weakens enamel, leading to dental caries.

Streptococcus ‘ mutans

The most common cause of cavities because it produces dextran.

Tartar

Calcified deposits of plaque.

Periodontal Disease

Inflammation and degeneration of structures that support the teeth.

Gingivitis

Infection of the gingiva (gums). Bleeding at brushing

Periodontitis

Chronic gingivitis where gums are inflamed and bleed easily, pus forms in tooth socket deteriotating the periodontal ligament loosing a teeth

Acute Necrotizing Gingivitis

Chewing is painful, extreme halitosis

Staphylococcal Food Poisoning

Caused by ingestion of S. aureus enterotoxins. Organism resistant to heat (everything) common in nasal passages , . proper refrigeration makes organism static

Shigellosis (bacterial dysentery)

Causative agent is a G- facultative anaerobe rod of the genus Shigella. Symptoms: diarrhea, internal hemorrhage

Salmonellosis (Gastroenteritis)

G-rod, facultative anaerobe, non-spore former; normal in the intestinal tracts of animals.

Divided in typhoid and non typhoid strains

Typhoid Fever

Causative agent is Salmonella typhi; found only in human feces, chronic carrier liver in gall bladder • symptoms like fever, headache, diarrhea. quinoles are used to treat it

Cholera

Causative agent is Vibrio cholera, a G-, flagellated curved rod that produces exotoxin. Secrete huge amounts of water and electrolytes → ↓bp = shock

Organism is destroyed by stomach acids

Traveler's Diarrhea

E. coli is most common cause

best treatment is rehydration therapy

Peptic Ulcers

Causative agent is Helicobacter pylori, can develop a ulcers or stomach cancer, there is a decrease in stomach mucus-produce high amounts of urease

C-dif

Causative agent is Clostridium difficile, a G+, spore forming obligate anaerobe rod that produces exotoxins. Antibiotics that disrupt normal flora, have symptoms like diarrhea, colitis, ulcerations of intestine. Fecal transplants

Mumps

Targets the parotid glands; saliva or respiratory transmission.

orchitis

Inflammation of testes can lead to sterility, MMR vaccine is a trivalent attenuated vaccine

HAV (Hepatitis A Virus)

Single stranded (SS) RNA virus without an envelope; food borne transmission; no chronic form.

HBV (Hepatitis B Virus)

Double stranded (DS) DNA virus with an envelope; not found in urine or feces but found in other body fluids.

HCV (Hepatitis C Virus)

SS RNA virus with envelope; often undetectable until chronic, then leads to liver cancer or cirrhosis.

HDV (Hepatitis D Virus)

SS RNA virus only found in those that already have HBV; increases the mortality rate of HBV patients.

HEV (Hepatitis E Virus)

SS RNA virus with an envelope; fecal/oral transmission; does not cause chronic liver disease.

Mycotoxins

Fungal toxins that cause blood diseases, nervous system disorders, kidney and liver damage, and cancer.

Giardiasis

Caused by a flagellated protozoan called Giardia intestinalis; attaches to the intestinal wall.

Amoebic Dysentery

Entamoeba histolytica is the causative agent; causes severe diarrhea containing RBCs. Abscesses the small intestine

Treated with metronidazole

Pharyngitis

Sore throat, can be bacterial or viral. Transmission is through inhalation of droplet nuclei.

S. pyogenes

A bacterial cause of pharyngitis, less than 10% of cases. If carrying a phage, it can cause Scarlet Fever.

Sinusitis

Inflammation of the lining of the sinus cavities, commonly caused by S. pneumoniae or H. influenza. Chronic conditions can lead to the formation of polyps.

Diphtheria

Caused by Corynebacterium diphtheriae infected with an exotoxin-producing phage. Damaged epithelial cells and ruptured red blood cells may block airways and cause suffocation. Death may result from pyelonephritis or myocarditis

Common Cold

Viral infection with a 2-4 day incubation period, caused by 200+ different viruses. Interferon can be used as a treatment. Person can predispose to secondary infection

Pertussis

Whooping cough, caused by Bordetella pertussis. Transmission is through inhalation of droplets. Organism colonizes on cilia in respiratory tract.

Pneumonia

Inflammation of lung tissue - can be bacterial, viral, fungal, or helminth. Also caused by chemicals, radiation, and allergies.

Mycoplasma pneumoniae

"Walking pneumonia" - usually milder form of pneumonia with a 12-14 day incubation period.

Legionnaire's Disease

Caused by Legionella pneumophilia, found in soil and water and becomes airborne. Symptoms can cause shock or kidney failure and can lead to death. No person-to-person transmission.

Tuberculosis

Caused by Mycobacterium tuberculosis. Multiplies inside WBCs of lungs. Hypersensitivity to skin tests indicates a + TB exposure. May attack digestive, urinary tract and meninges

Influenza

Orthomyxovirus virus - RNA virus. Enters through inhalation - symptoms appear 36-48 hours after infection.

Hanta Virus

Carried by rodents - shed in their feces/urine - becomes airborne in dust.

Coccidioidomycosis

Causative agent is a soil-borne fungus Coccidioides immitis. Transmission is through inhalation of dust particles containing fungal spores.

Pneumocystis

Causative agent is Pneumocystis carinii-fungus. Thickens the alveoli - makes air exchange difficult. Causes more damage in compromised patients.

Septicemia

Proliferation of microbes in the blood, creating a toxic condition. If endotoxins produced could cause systemic vasodilation → ↓bp = shock

Sepsis

A toxic condition caused by the proliferation of microbes in the blood.

Childbirth Fever

Uterine infection, often caused by Streptococcus pyogenes after childbirth / abortion could progress to pneumonia → septicemia

Endocarditis

Inflammation of the heart, often caused by Streptococcus species. Bacteria released in tooth/tonsil extraction

Acute Endocarditis

Rapid destruction of heart valves caused by S. aureus infection.

Rheumatic Fever

Autoimmune disease resulting from an S. pyogenes infection that damages heart valves and joints.

Lyme Disease

Causative agent is Borrelia burgdorferi, transmitted by deer ticks and often characterized by a bull's-eye rash.

Plague

Causative agent is Yersinia pestis, transmitted by flea bites, squirrels bacteria can damage lymph nodes, axillary

Tularemia

“rabbit fever” Causative agent is Francisella tularensis, infection through inhalation, ingestion, bites or minor cuts .10 bacteria are needed to cause disease → can lead to death

Anthrax

Causative agent is Bacillus anthracis, atypical capsule that doesn't stimulate the immune system.Endospores survive up to 60 years in the soil -can enter through inhalation/cutaneous

Gangrene

Infection caused by Clostridium perfringens in wounds with interrupted blood supply, leading to tissue necrosis & gas formation.

Rocky Mountain Spotted Fever

Causative agent is Rickettsia rickettsii, transmitted by ticks, causing high fever and a macular rash in palms and soles. Death could result from kidney to heart failure

Cat Scratch Fever

Causative agent is Bartonella henselae, often transmitted by cat scratches, leading to inflammation and swollen lymph nodes.

Malaria

Causative agent is a protozoan of the genus Plasmodium, transmitted by mosquitos, infecting liver and red blood cells. Cases worldwide, kills more African Childs

Leishmaniasis

Caused by one of 20 different protozoan species and transmitted by sandflies causing lesions on the skin, internal organs and mucous membranes.

Toxoplasmosis

Causative agent is Toxoplasma gondii, a spore-forming protozoan transmitted through cat feces or undercooked meat, causing cysts in soft tissue. Dangerous to fetus can cross the placenta

Trypanosomiasis

Causative agent is Trypanosoma cruzi, a flagellated protozoan transmitted by the Kissing Bug and blood transfusions , damaging the heart, lungs, and esophagus.

Schistosomiasis

Causative agent is a fluke (helminth) of the genus Schistosoma sp, causing granulomas due to the body's response to the eggs. Water contaminated with urine or feces - larva penetrates skin

Infectious Mononucleosis

Causative agent is the Epstein Barr Virus (EBV), transmitted through saliva, causing symptoms due to the T cell response to the virus.

Ebola

Caused by a Filovirus, causing hemorrhagic symptoms with a high mortality rate.

Hanta Virus

Causative agent is the Sin Nombre virus, transmitted by airborne dust contaminated with rodent urine/feces, causing a pulmonary infection.

Stratified Squamous Epithelial Tissue

Keratinized; serves as the first line of defense when not compromised.

Dermis

Contains hair follicles, sweat glands, and oil glands; pores serve as a portal of entry for microbes.

Perspiration

Contains salt, lysozyme, and antimicrobial peptides.

Sebum

Oil produced by the skin; nutritive for some microbes.

Mucous Membranes

Line cavities that open to the outside; often acidic for protection; eyes washed with tears containing lysozyme.

Normal Microbiota of Skin

Most survive drying and salt concentrations; includes Staphylococcus epidermidis and Micrococcus luteus.

Microbes in axilla and groin

Metabolized the lipids /proteins on skin , creates odor

Diphtheroids

G+ pleomorphic Corynebacterium Xerosis, proprionbacterium acne's

Dandruff

Fungal infection of scalp

Skin Lesion - Vesicle

Small, fluid-filled lesion.

Skin Lesion - Bullae

Vesicle greater than 1 cm.

Skin Lesion - Macule

Flattened red lesion.

Skin Lesion - Papule

Raised lesion.

Skin Lesion - Pustule

Papule that contains pus.

S. epidermidis

Common on the skin; can form a biofilm during catheter use.

S. aureus

found in nasal passages; has pigment to protect from UV light, coagulase+ - produces enterotoxins

Folliculitis

Inflammation of a hair follicle; pimple.

Sty

Staph infection of eyelash

Furuncle

"Boil"; localized region of pus; a type of abscess.

Impetigo

Often caused by S. aureus or Streptococcus pyogenes; usually enters through a break in the skin.

Scalded Skin Syndrome

Form of impetigo caused by S. aureus; causes exfoliation; common in infants.

Toxic Shock Syndrome

Fever, vomiting, sunburn-like rash, shock, organ failure, death; associated with tampons, surgical procedures, abortions.

Streptococcal

Cause of meningitis, pneumonia, sore throat, ear infection, endocardium, dental caries. Produce hemolysis

S. pyogenes

Beta-hemolytic; M protein provides protection from phagocytosis and adheres to host cells.

Necrotizing Fasciitis

Caused by strep infection; can become systemic; high mortality rate.

Pseudomonas aeruginosa

Common opportunistic organism; produces exotoxins and endotoxins; forms blue-green biofilms.

Warts

Caused by HSV-1, incubation time of several months, not caused by frogs/toads

Smallpox

Respiratory transmission; forms lesions; declared eradicated in 1980.

Monkey Pox

Transferred from monkey to monkey; not monkeys to humans.

Chicken Pox

Caused by Varicella zoster virus; respiratory transmission; may lay latent in PNS and cause shingles.

Herpes Simplex I (HSV I)

Oral or respiratory transmission; causative agent of cold sores; may lay latent in cranial nerve V.

Measles (Rubeola)

Respiratory transmission; vaccine is MMR; complications can lead to encephalitis or pneumonia.

Rubella (German Measles)

Milder case; respiratory transmission; may cause birth defects during the 1st trimester.

Dermatomycosis

Fungal infections of the epidermis; examples include athlete's foot, jock itch, and ringworm.

Candidiasis

Causative agent is Candida albicans; may overgrow mucous membranes when normal flora is disrupted; common in immunosuppressed individuals.

Scabies

Caused by mites that burrow into the skin and lay eggs; transmitted by contact.

Lice

Adults live about 30 days; produce egg cases designed to attach to hair; some have become resistant to OTC treatments.

Ophthalmia neonatorum

Caused by Neisseria gonorrhea; causes conjunctivitis and blindness.