Chs 24–26 Digestive, Cardiovascular, Nervous, Urinary & Reproductive Systems Review

57 Question-and-Answer flashcards covering key pathogens, diseases, characteristics, reservoirs, and clinical signs from Chapters 24–26 of the lecture notes.

What bacterium is primarily responsible for tooth decay and how does it damage teeth?

Streptococcus mutans forms plaque (dextran) and produces lactic acid that dissolves enamel and dentin.

How does gingivitis differ from periodontitis?

Gingivitis is a reversible gum inflammation; periodontitis is a chronic infection that destroys the periodontal ligament and alveolar bone, often leading to tooth loss.

What organism and toxin cause staphylococcal food poisoning?

Ingestion of a heat-stable enterotoxin preformed by Staphylococcus aureus in contaminated food.

Which symptom distinguishes shigellosis from salmonellosis?

Shigellosis produces bloody, mucous (dysenteric) stools, whereas salmonellosis usually causes watery diarrhea without blood.

Name two major diseases produced by Salmonella spp.

Salmonellosis (gastroenteritis) and typhoid fever; Salmonella can also cause bacteremia/septicemia.

What is the causative agent of cholera and its hallmark clinical sign?

Vibrio cholerae; profuse "rice-water" stools leading to rapid dehydration.

List three important diseases caused by pathogenic Escherichia coli strains.

Traveler’s diarrhea, hemorrhagic colitis/hemolytic uremic syndrome (EHEC O157:H7), and infantile diarrhea; E. coli is also a major cause of UTIs.

What is the main animal reservoir for Campylobacter gastroenteritis?

Poultry (chickens, turkeys) as well as cattle and household pets.

Which bacterium causes peptic ulcer disease and what enzyme helps it survive stomach acid?

Helicobacter pylori; it produces urease to neutralize gastric acid.

What domestic animal is the principal reservoir for Yersinia gastroenteritis?

Pigs (swine).

Why is mumps classified as a digestive system disease?

Because the virus infects and inflames the parotid salivary glands, organs involved in digestion.

How is hepatitis A transmitted and does it become chronic?

Fecal-oral transmission; it causes an acute illness that does not progress to chronic liver disease.

What distinguishes hepatitis B from hepatitis C?

HBV is a DNA virus with a vaccine and may be acute or chronic; HCV is an RNA virus, often becomes chronic leading to cirrhosis and cancer, and has no vaccine.

Name two fungal intoxications or infections that affect the digestive tract.

Ergot poisoning (Claviceps purpurea) and aflatoxin poisoning (Aspergillus flavus); oral candidiasis is another example.

Give three protozoan diseases of the digestive system.

Giardiasis, amebiasis (Entamoeba histolytica), and cryptosporidiosis (Cryptosporidium spp.).

Provide four helminthic infections of the gastrointestinal tract.

Ascariasis, tapeworm (Taenia spp.) infection, pinworm (Enterobius vermicularis), and hookworm (Necator americanus/Ancylostoma duodenale).

What bacterium causes puerperal sepsis and what is the usual portal of entry?

Streptococcus pyogenes entering the uterus during or shortly after childbirth.

Which immune-mediated disease follows Streptococcus pyogenes throat infection and can damage heart valves?

Rheumatic fever.

Identify the bacterium responsible for tularemia and its typical zoonotic source.

Francisella tularensis; infection from rabbits, rodents, or tick/deer-fly bites.

What genus of small gram-negative coccobacilli causes brucellosis (undulant fever)?

Brucella spp. (e.g., B. abortus, B. melitensis, B. suis).

State the etiologic agent of anthrax and its three clinical forms.

Bacillus anthracis; cutaneous, gastrointestinal, and inhalational anthrax.

Which anaerobic bacterium produces toxins that result in gas gangrene?

Clostridium perfringens.

What bacterium transmitted by cat scratches leads to swollen lymph nodes?

Bartonella henselae (cat-scratch disease).

Name the two causative agents of rat-bite fever.

Streptobacillus moniliformis (North America) and Spirillum minus (Asia).

What pathogen is responsible for plague and how is it transmitted?

Yersinia pestis, transmitted by infected rat fleas (Xenopsylla cheopis).

What spirochete causes Lyme disease and what is the characteristic early sign?

Borrelia burgdorferi; the erythema migrans "bull’s-eye" rash.

Which rickettsial disease is characterized by a spotted rash on palms and soles?

Rocky Mountain Spotted Fever caused by Rickettsia rickettsii.

Burkitt’s lymphoma and infectious mononucleosis are both associated with which virus?

Epstein-Barr virus (human herpesvirus 4).

List four viral hemorrhagic fevers of medical importance.

Ebola, Marburg, Lassa, and yellow fever (dengue and Hantavirus illnesses are also hemorrhagic fevers).

Which protozoan species cause malaria and what vector transmits them?

Plasmodium falciparum, P. vivax, P. ovale, P. malariae; transmitted by Anopheles mosquitoes.

What protozoa cause leishmaniasis and what insect vector spreads the disease?

Leishmania donovani, L. tropica, L. braziliensis; spread by female phlebotomine sandflies.

What parasitic trematodes cause schistosomiasis?

Schistosoma mansoni, S. haematobium, and S. japonicum.

Describe the classic clinical presentation of Bell’s palsy.

Sudden unilateral facial paralysis with drooping mouth, inability to close the eye, and possible pain behind the ear.

Differentiate the central nervous system (CNS) from the peripheral nervous system (PNS).

The CNS comprises the brain and spinal cord; the PNS includes all nerves and sensory receptors outside the CNS.

Define meningitis, encephalitis, and meningoencephalitis.

Meningitis: inflammation of meninges; encephalitis: inflammation of brain tissue; meningoencephalitis: inflammation of both meninges and brain.

Name three leading bacterial causes of acute meningitis.

Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae type b (Listeria monocytogenes is also significant).

List common symptoms of bacterial meningitis.

Fever, severe headache, stiff neck, nausea, vomiting, photophobia, and possible convulsions or coma.

Which organism produces tetanospasmin and what is the hallmark symptom?

Clostridium tetani; rigid muscle spasms including lockjaw.

What bacterium produces botulinum toxin and what type of paralysis results?

Clostridium botulinum; causes flaccid (descending) paralysis.

Give two approved therapeutic uses for purified botulinum toxin (Botox).

Cosmetic reduction of facial wrinkles and treatment of muscle spasticity (e.g., cervical dystonia); it is also used for chronic migraine and hyperhidrosis.

Identify the pathogen that causes leprosy and the body system it primarily attacks.

Mycobacterium leprae; infects peripheral nerves and skin.

What virus causes poliomyelitis and what neurons does it destroy?

Poliovirus; destroys motor neurons of the spinal anterior horn, leading to paralysis.

Which virus causes rabies and what clinical sign is virtually pathognomonic?

Rabies virus (genus Lyssavirus); hydrophobia (throat muscle spasms when attempting to drink).

What are the two most serious arboviral encephalitides in humans in North America?

Eastern equine encephalitis (EEE) and West Nile encephalitis.

Name the two subspecies of Trypanosoma that cause African sleeping sickness.

Trypanosoma brucei gambiense (chronic) and T. b. rhodesiense (acute).

What is the causative agent of Creutzfeldt-Jakob disease and how does it damage the brain?

Misfolded prion proteins that produce spongiform degeneration, leading to rapid dementia.

Match each urinary tract inflammation with the structure involved: urethritis, ureteritis, cystitis, pyelonephritis.

Urethritis—urethra; ureteritis—ureter; cystitis—urinary bladder; pyelonephritis—kidney (renal pelvis).

What organism accounts for most uncomplicated urinary tract and bladder infections?

Escherichia coli.

Identify the spirochete responsible for leptospirosis and mention a severe form of the disease.

Leptospira interrogans; severe icteric form is Weil’s disease involving liver and kidney failure.

State the causative agent of gonorrhea and one characteristic symptom in males.

Neisseria gonorrhoeae; purulent urethral discharge with painful urination.

Which obligate intracellular bacterium causes the most common bacterial STD, chlamydia?

Chlamydia trachomatis (serovars D–K).

Pelvic inflammatory disease is most commonly caused by which two pathogens?

Neisseria gonorrhoeae and Chlamydia trachomatis.

Name the spirochete that causes syphilis.

Treponema pallidum.

Which pathogen causes chancroid and what is the lesion like?

Haemophilus ducreyi; produces a painful "soft" chancre ulcer on genitalia.

What bacterium causes bacterial vaginosis and what microscopic finding is diagnostic?

Gardnerella vaginalis; the presence of "clue cells" (epithelial cells covered with bacteria).

What virus causes genital herpes and what is the typical lesion?

Herpes simplex virus type 2 (or HSV-1); clusters of painful vesicles/ulcers on genital mucosa.

Which viral family causes genital warts and what malignant complication can arise?

Human papillomavirus (HPV); high-risk types (e.g., 16 and 18) can lead to cervical and other anogenital cancers.