Infections of the Genitourinary System

1. Infections of the Genitourinary System In general there are no microbes found in the upper part of the urinary tract and urine is generally sterile (due to low pH, salt and urea). But the lower part of the urethra does have normal flora. These organisms include: Lactobacillus, coagulase-negative Staphylococcus, diphtheroids, Hemophilus, Streptococcus, and Bacteroides.

2. In females, the normal flora and susceptibility to infection varies with the ovarian cycle. When estrogens are present, the vagina is more acidic (due to the metabolism of glycogen by Lactobacilli) and thus less susceptible to infection.

3. Urinary Tract Infections Causes include enterobacteria (like E. coli causing about 80% of cases), Staphylococcus saprophyticus, Pseudomonas, and Enterococcus. Cystitis in women is often accompanied by dysuria (pain or burning during urination) and may lead to kidney infections (pyelonephritis). Symptoms of cystitis include: burning sensation during urination, urgency, frequency, and an odor. Glomerulonephritis AKA Bright’s Disease causes inflammation of the kidneys that leads to damage in some cases it even leads to kidney failure. This is a common nosocomial infection that is an important source of fatalities (especially when it spreads to the kidneys causing pyelonephritis with fever, chills vomiting, back pain, blood in urine etc. or glomerulonephritis Women are predisposed to UTIs (urinary tract infections) due to their short urethras, sexual intercourse, and use of diaphragms. Older men become more susceptible as their prostates enlarge. The presence of a catheter also increases susceptibility.

4. Diagnosis- urinalysis, culture and isolation Treatment- antibiotics Prevention- drinking plenty of fluids and for women and girls wiping front to back. Bladder Infections Part II

5. Leptospirosis Part I Cause Leptospira interrogans Leptospirosis is a zoonosis (lots of animals carry it- dogs, cows, rats, cats etc. and pass the bacterium in their urine) and is spread to the urinary system from the bloodstream. The bacterium enters the body through mucous membranes (of the eye, nose, or mouth) or through breaks in the skin. Often asymptomatic, but the mortality rate for more severe cases when untreated can be as high as 30%. Onset is abrupt and includes headache, fever, chills, redness of the eyes. Most recover, but in some, symptoms reoccur and they may have bleeding from various sites, confusion and organ damage. In fact, about 5-30% of untreated cases result in death. Fewer than 100 cases are reported in the U.S. /year.

6. DX- culture and isolation on special media and extended incubation times TX- antibiotics (e.g., tetracycline) before the 4th day of infection Prevention- avoid contact with non-human animal urine, and vaccinate pets Leptosporosis Part II

7. Gonorrhea Part I Cause - Neisseria gonorrhoeae Humans are the only reservoirs of infection. It is among the most prevalent of the STIs but the incidence has been decreasing over the last 15 years (there are about 342,000 cases/year). Infections can also occur in the throat or anus. Moreover, the organism can survive for weeks in dried masses of pus (yuck). The ID (infectious dose) is relatively small. In males, the infection is often symptomatic causing painful urination and pus formation and can be self-limiting. In women the disease can be asymptomatic for a long time with complications: PID (leading to sterility or ectopic pregnancies) and eye infections in newborns (ophthalmia neonatum); eye infections can even occur in adults. Untreated infections in males can also lead to sterility due to orchitis and also lead to UTIs. Systemic infections (disseminated gonococcal infection, DGI) can occur. Gonococcal arthritis is the most common cause of joint infection in 16-50 year old people. Antibiotic resistance is increasing in this organism.

8. Gonorrhea Part II Dx - in males a Gram stain on material obtained from the urethra, in females culture on special media, or molecular probes Tx – antibiotics Prevention – monogamy, safe sex (consistent and proper use of condoms), abstinence, there is no vaccine

9. Nongonococcal urethritis (NGU) mostly chlamydial infections Cause - Chlamydia trachomatis Humans are the only reservoirs. Like gonorrhea, there are infections of the genital tract and eye (acquired during birth or interestingly enough from non-chlorinated swimming pools). This STI is the most common with 4 million cases/year. In males, the manifestations are a nongonococcal urethritis. In females who are symptomatic, a cervicitis occurs which is characterized by vaginal discharge, endometritis, in some cases painful urination, abnormal vaginal bleeding, and abdominal painand also PID. Infants born to women who are infected can develop pneumonia (usually not until 2-3 months after birth) or eye infections (but the same drops used to prevent gonococcal eye infection in infants prevent chlamydial infections).

10. Dx - tissue culture or serological testing Tx – antibiotics Prevention – monogamy, safe sex (condoms) and abstinence There are other organisms that cause nongonococcal urethritis Nongonococcal urethritis (NGU) mostly chlamydial infections Part II

11. Syphilis Part I Cause - Treponema pallidum Humans are the only natural reservoirs. Syphillis is called the great imitator due to the similarity between some of the symptoms and other diseases. The risk of infection when having intercourse with an infected person is 12-30% and transmission usually involves sexual intercourse, but it can be transmitted (rarely) by kissing. However, there was a dramatic decrease in new cases in 1990. Less commonly, it can be passed from mom to fetus in utero causing congenital syphilis and by blood transfusion. Although the ID is not known, it is thought to be small.

12. Syphilis is a systemic infection with the following clinical manifestations: (1) primary syphilis is characterized by a chancre at the site of infection. The chancre progresses from a small, red, hard bump to an enlarged lesion with a shallow crater surrounded by firm margins. Chancres most commonly occur on the genitalia (and are painless at this site) but may also occur on the lips, nipples, fingers etc. The chancre heals in about 4-6 weeks Syphilis Part II

13. (2) After the primary latent period, the disease then progresses to the next stage. (3) Secondary syphilis occurs about 3 weeks to 6 months after the chancre heals. The disease is now systemic and this stage is characterized by fever, headache, sore throat and a peculiar red or brown rash that disappears in a few weeks (in general). Syphilis Part III

14. (4) After these symptoms disappear, @ 30% of those infected will enter a highly varied secondary latent period (up to more than 20 years). (5)The final or tertiary syphilis is rare due to the use of antibiotics (to treat other infections ). Tertiary syphilis is characterized by a variable combination of: cv problems, gummas (soft granulomas) of the liver, bones, skin, and neurosyphilis giving rise to severe headaches, convulsions, derangement, blindness, and loss of coordination Syphilis Part IV

15. Dx - serology, dark-field microscopy, fluorescent antibody, and treponemal immobilization tests Tx – antibiotics Prevention - safe sex, and abstinence Congenital syphilis Syphilis Part V

16. Caused by Haemophilus ducreyi. The manifestation is a single or multiple genital sore(s) that are painful (unlike the chancre of syphilis). It can spread to the groin area and cause large buboes (not plague bubos) It is more common in other countries than in the U.S. (about 100 cases/yr in U.S.). Dx involves the identification of the organism from the lesions or fluid from the lesions. Although it is often self-limiting, antibiotics are used for treatment because the lesions heal more rapidly with treatment. Chancroid

17. Genital Herpes Part I Cause - herpes simplex virus usually type 2 This is among the top four most common STIs and rarely non-sexual transmission occurs. Symptoms include itching, burning, and in women sometimes pain. Then vesicles occur and ulcerate. Like oral herpes infections, these become latent and then reoccur. A complication is a congenital infection called neonatal herpes that can be fatal or cause brain damage and that is acquired from mom which can be prevented in most cases by a C-section. In addition, the risks of cervical cancer increases in women with herpes. Herpetic whitlow can also occur

18. Dx - tissue culture Tx - of symptoms with medication such as acycclovir that decreases the severity of the disease and the incidence of recurrences. Prevention – monogamy, safe sex helps but condoms do not eliminate the chance of transmission, and abstinence Genital Herpes Part II

19. Genital Warts Part I Cause – papillomaviruses Genital warts are one of the most common STIs in the US (at least ½ of sexually active men and women become infected at some point during their lifetime) The warts are unsightly or they mayasymptomatic or silent. The silent types have been linked to an increased risk of cancer (cervical and penile). However, the warts do not always develop but the person is still infected. Infected mothers occasionally transmit these warts to their babies that cause infections of the respiratory tract.

20. Genital Warts Part II Dx – symptoms, a new screening test that replaces the original pap smear, DNA tests can determine if someone is infected with a strain linked to cancer. Tx - wart removal Prevention - safe sex and abstinence, although condoms do not work as well in preventing the transmission of these viruses

21. Acquired Immunodeficiency Disease (AIDS) Part I Cause - Human Immunodeficiency Virus AIDS is one of the biggest concerns worldwide due to the high mortality associated with it. It is among the leading causes of death in young adults. It cripples the immune system and thus infections occur that are eventually fatal. It is estimated that 1 to 2 million Americans are infected with HIV and perhaps as many as 9 million. World-wide it is estimated that 4.8 became infected in 2003. In that same year, 2.9 million died.

22. Dx – serology Tx - new drugs prolong life but so far there is no cure Prevention - safe sex and abstinence, universal blood and body fluid precautions, and screening blood and tissue donors. AIDS Part II

23. Vulvovaginal candidiasis Candida albicans Characterized by itching and sometimes a rash on the external genitalia of women. However, it is sometimes asymptomatic. Antibiotic therapy, pregnancy, diabetes and the use of oral contraceptives are predisposing factors. Dx - the presence of budding yeast in a vaginal smear Tx - Antifungal medications Prevention – safe sex

24. Cause - Trichomonas vaginalis Not always symptomatic but when it is symptoms are most likely to occur in women (burning, itching, and a yellowish discharge). Humans are the only reservoirs but the parasite can survive for short periods of time in other moist environments and thus is occasionally transmitted nonsexually. There are about 7.4 million cases in the U.S./year. Dx - presence of the parasite in vaginal smear Tx - antiparasitic drugs (Flagyl) or douching with vinager. Prevention - safe sex and abstinence Trichomoniasis or Trich

25. Cause - Staphylococcus aureus Symptoms of TSS include fever, diarrhea, muscle aches, and a rash. It is caused by the production of toxins and is exacerbated by the use of highly absorbent tampons (or tampons that are left in for long periods of time) that result in a decrease in the amount of Magnesium in the vagina. The contraceptive sponge also caused some cases of TSS and was taken off of the market. Dx - culture and isolation Tx - antibiotics Prevention - frequent changing of tampons Toxic Shock Syndrome

26. occurs when the normal flora of the vagina are compromised and is caused by opportunists. Bacterial vaginitis

27. Caused by Gardnerella vaginalis in combination with anaerobic bacteria e.g, Bacteriodes. It is characterized by a grayish-white, slightly bubbly discharge from the vagina, an odor, decrease in the pH of vaginal secretions, and the presence of clue cells. Flagyl helps by killing the anaerobes and allowing the lactobacilli to recolonize the vagina. Douching with yogurt can also be used to treat this vaginalis. Gardnerella vaginalis

28. (e.g.,lice AKA crabs, scabies, caused by mites) are also common. Multicellular parasites

29. Infections of the Nervous System

30. The Nervous System is composed of two main parts: Central Nervous System (CNS) and Peripheral Nervous System (PNS) Human Nervous System

31. Fluid is present in the meninges and also circulates through the ventricles of the brain. This Cerebrospinal Fluid (CSF) is normally sterile Cerebrospinal Fluid

32. Meningitis (bacterial) Cause - there are several species of bacteria that cause meningitis including Escherichia coli, other Enterobacteriaceae and streptococci (leading causes in newborns), Streptococcus pneumoniae, and Staphylococcus (leading causes in adults), Hemophilus influenzae, and Neisseria meningitidis (leading causes in preschool age children), and N. meningitidis and S. pneumoniae (leading causes in youth and young adults. It is a life-threatening condition. Mortality of meningococcal meningitis is 1% with the best treatment, but 15% with delayed treatment and 85% with no treatment. Death can occur in 12-18 hours if treatment is delayed. The mortality rate for pneumococcal meningitis is 40%. Another bacterium that sometimes causes outbreaks of meningitis is Listeria monocytogenes. Most cases of meningitis occur in children under five. This disease is very serious and can be rapidly fatal (esp. meningococcal meningitis). Symptoms include severe headache, fever, and intense pain of the neck and back. A petechial rash can occur with meningococcal meningitis. The disease causes tissue necrosis, blood clotting, edema of the brain, decreased spinal fluid, flow and impaired function.

33. Dx - culture and isolation and Gram Stains of CSF Tx – antibiotics without delay Prevention - there are vaccines for some of the bacteria or some strains of some species. For meningococcal meningitis, prophylactic antibiotics are administered to contacts.

34. Listeriosis Part I Cause Listereria monocytogenes Symptoms- flu-like with or without gastrointestinal involvement, meningitis In pregnant women it causes miscarriage. Transmission is most likely by consuming improperly processed dairy and meat.

35. DX- Culture of fluids e.g., CSF TX- antibiotics ASAP Prevention. Involves proper food handling and pasteurization and new bacteriophage sprays for food. Listeriosis Part II

36. Leprosy (Hansen’s disease) Cause - Mycobacterium leprae Leprosy is a common (but less common than before, with less than 2.5 million active cases worldwide; 10 million people have been cured over the past 15 years) disease. Humans and armadillos are the reservoirs. Health and living conditions are predisposing factors. After exposure, the macrophages of most people destroy the bacteria. If not, the incubation is commonly 2-5 years, but can be as long as 20 years. The possible forms of the disease include : (1) tuberculoid leprosy which is the most superficial form with shallow painless solitary lesions, and (2) lepromatous leprosy is characterized by the formation of disfiguring lepromas (figs. 24.7-24.8). Lepromatous leprosy can result in the erosion of tissues and bone.

37. Dx - Acid fast stain, PCR, and feather test for loss of sensitivity. Tx – antibiotics Prevention - sanitary living conditions, handwashing, but no vaccine. However, there is a group of people, The Global Alliance for Leprosy Elimination whose goal is to treat and cure all leprosy patients worldwide by distributing antibiotics FREE.

38. Tetanus Part I Cause Clostridium tetani The bacterium causes tetanus when it enters deeply into tissues by puncture wounds. It is common in soil and even in the feces of many mammals. A powerful toxin is responsible for the disease whose symptoms include: generalized muscle stiffness, then spasms, the muscles of the jaw often experience sustained contraction (tetany) resulting in “lockjaw”. Other common symptoms are clenched fists and arched back (figure 24.10). Neonatal tetanus is one of the top ten infectious disease killers worldwide despite the fact that it could be prevented by vaccination.

39. Tetanus Part II DX- symptoms TX- antitoxin, antibiotics Prevention- Vaccination

40. Botulism • Cause - toxins of Clostridium botulinum Botulism is an intoxication associated with eating poorly preserved foods (or more rarely: by colonization of the human intestine or wound infections). The spores gain access to the food products which are inadequately cooked in a pressure cooker that does not reach sufficient pressure and temperature, canned (and thus anaerobic conditions exist for germination and growth), and then contamination with the toxin botulin (the most powerful toxin known to man). Symptoms appear 12-36 hours after eating the toxin that prevents neural impulse transmission. Nausea and vomiting may not occur but the muscles of the head are affected first resulting in double vision, and difficulty in swallowing and speaking. Later symptoms involved descending paralysis. The fatality rate has dropped due to the use of technology (e.g., respirators) but is still about 25%.

41. Dx - symptoms and identification of toxin Tx – antitoxin Prevention - proper canning techniques and adequate heating of food before eating.

42. Viral Meningitis and Encephalitis Cause - various viruses can cause meningitis and encephalitis, some cases are sporadic that result from viruses that cause other diseases (e.g., mononucleosis), and some are arthropod borne and spread by the bites of insects. Some viruses cause epidemics of these diseases. Symptoms include: fever, headache, stiff neck, disorientation, and seizures and coma. Although some people die, most recover but some are left with disabilities.

43. Dx - rule out bacterial encephalitis Tx - symptoms Prevention - for the arthropod borne forms avoiding biting insects (especially mosquitoes) and use repellents

44. Poliomyelitis Cause – three types of poliovirus The first symptoms mimic meningitis followed by pain and spasms of some muscles and later, paralysis. The virus enters the mouth and infects the throat and intestine then the blood. This disease is interesting in that areas with poor sanitation, babies develop immunity and thus do not suffer the severe sequel (paralysis), but in areas with good sanitation, natural immunity does not exist and many children can suffer paralysis. Post polio syndrome can occur 10-50 years after infection and which can result in severe disability.

45. Dx – cultures from throat and feces Tx – treat symptoms, in the past iron lungs were used for ventilation Prevention- vaccination. Polio Part II

46. Rabies Cause - a rhabdovirus Rabies is not common in humans but when it does occur it is often fatal (only two people have been known to survive and recover) after the symptoms appear (50% die within 4 days after symptoms appear and others soon afterwards). It results from a bite by an infected non-human animal (remember Cujo). Symptoms begin (after a long incubation time up to six years) with a fever, sore throat, headache, muscle aches, fatigue, and nausea then progress to an encephalitis, agitation, confusion, hallucinations, seizures, and sensitivity to light, touch, and sound. Then a high fever and frothing at the mouth occur. There are 0-4 human cases of rabies in the US each year and about 5,000 wild animal cases each year but the number of cases in wildlife have been increasing. Cats are the most common domestic animals affected in the U.S. The susceptibility of the animal to the virus depends on the species. For example many bats are symptomatic but foxes succumb to the disease.

47. Dx - fluorescent antibody staining of smears from conjunctiva, fatty tissue of the neck or tissue from the brain. Tx - After symptoms begin - none, vaccination as soon as possible after exposure Prevention - the vaccination of domestic animals and avoiding suspicious animals Rabies Part II

48. Cause - Cryptococcus neoformans This fungus primarily gains access via the respiratory system. In healthy individuals it cause a subclinical an rapidly resolved respiratory infection or develop into a serious disease but very slowly. In the immunocompromised the fungus can spread to the CNS with a significant mortality rate. Dx - India ink preparation (a wet mount) and culture Tx - antifungal medications Prevention – none really except avoidance of bird droppings Cryptococcal meningoencephalitis

49. African Sleeping Sickness Cause - Trypanosoma brucei The vector is the tsetse fly. After a bite, a nodule appears at the site, then lymph nodes may enlarge. After this the symptoms may disappear. Weeks to years later, cyclic fevers occur. AS the CNS becomes involved, apathy, decreased activity, slurred speech, coma and eventually death occur. There are about 10,000-20,000 new cases each year. Dx - presence of the parasite in stained blood, tests for antibodies. Tx - antiparasitic drugs, but the more advanced the lower the TI and the increased serious side effects. Prevention - avoidance of vector

50. Cause - Naegleriafowleri, and Acanthoamoeba These free-living amoebas cause a rare but in most cases, fatal infection. Naegleria gains entry through the nasal passages while a person is swimming. Dx - presence of the parasite in CSF Tx – not usually effective, five survivors reported, antifungal, Amphotericin B, can be used Prevention - avoid swimming in stagnant waters Ameobic meningoencephalitis