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UROGENITAL AND SEXUALLY
TRANSMITTED DISEASES
CHAPTER 20
Copyright © 2012 John Wiley &
Sons, Inc. All rights reserved.
A. There are lots of mechanisms by which steroids dampen the immune
response. Here are a few of them:
1. Suppression of T cells. Steroids interfere with production of cytokines (like
interleukins), which are critical in the proliferation and interaction of T cells.
2. Suppression of B cells. Steroids interfere with the binding of interleukins to
B cells, which means that the B cells have a hard time proliferating and making
antibodies.
3. Suppression of neutrophils. Steroids inhibit just about everything that
neutrophils do: adhesion, chemotaxis, phagocytosis, and the release of toxic
substances.
4. Suppression of macrophages. Steroids down-regulate the expression of Fc
receptors on macrophages – so macrophages are less able to phagocytose
opsonized things.
5. Diminished production of prostaglandins and leukotrienes. Steroids inhibit
cyclooxygenase and phospholipase A2, which decreases the production of proinflammatory arachadonic acid metabolites.
Steroids are used in a ton of different immune and inflammatory disorders, like
asthma, vasculitis, arthritis, gout, multiple sclerosis, sarcoidosis, alopecia
areata…the list goes on and on.
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Listeria in Sabra Hummus Prompts New Wave of Recalls Two food manufacturers
have issued nationwide recalls of products because of the discovery of the potentially
lethal bacterium listeria, which federal authorities have now linked to three deaths
and five illnesses in Texas and Kansas. On Wednesday, the Sabra Dipping Company
recalled 30,000 cases of its classic hummus after several tubs in Michigan tested
positive for the food-borne bacteria. No illnesses related to the hummus have been
reported so far, according to Jennifer Holton, a spokeswoman for the Michigan
Department of Agriculture and Rural Development. Separately, the Centers for Disease
Control and Prevention has confirmed that three people in Texas fell ill after eating
Blue Bell ice cream from 2011 to 2014. The agency had already connected the
company with three listeria-related deaths and two additional cases. Listeria is among
the most dangerous food-borne illnesses, particularly to people with compromised
immune systems, although it is much more rare than other common diseases like
salmonella poisoning. The C.D.C. estimates that about 380 people die of salmonella
every year, which translates to less than 1 percent of about one million annual cases.
About 260 people, or about 16 percent of about 1,600 cases, die of listeria every year.
We are concerned that there may be contaminated ice cream still in people’s freezers,”
Dr. Tauxe said. “It appears that products from the Oklahoma facility may have been
contaminated for some time.” An outbreak of listeria traced to cantaloupe killed 33
people in 2011 and sickened more than 140 others. In March, a district court judge
approved settlements for the families of 30 people who died.
Researchers identify antibodies to fight Marburg virus Two new studies have
demonstrated how human antibodies can neutralize the Marburg virus, a highly lethal
virus related to Ebola. Antibodies have been found to bind to the surface of the virus,
which could lead to future antibody treatments and vaccines to target Marburg and
other viruses in the family. Marburg virus is up to 90% lethal. Just like the Ebola virus,
it can cause hemorrhaging and organ failure. An outbreak of the virus in Angola in
2005 was responsible for the deaths of 329 people, and the worry is that an even
bigger outbreak could occur in the future. "The good news is, humans do make
antibodies when they are infected that can kill these viruses... which suggests that
vaccines should work," says Dr. James Crowe, lead author of one of the two studies
published in Cell. Due to the relationship between the Marburg and Ebola viruses, the
researchers questioned whether the antibody would be able to neutralize Ebola in the
same manner as this. "These cross-reactive antibodies are a straightforward route to
a therapeutic," she says. "You could use these antibodies directly against Marburg
virus or - with a bit more engineering - use them to also target Ebola virus."Part of
why the viruses are so dangerous is because of how long it takes the body's immune
system to effectively respond to their attack - around 4-6 weeks. According to Dr.
Crowe, antibody injections shortly after exposure could be enough to prevent illness
from fully developing.
Urogenital diseases usually not transmitted sexually
Urinary tract infections (UTI’s) are among the most common of all
infections seen in clinical practice.
Second only to respiratory infections, they account for 3 million office visits per year in the
Organisms: E. coli is the causative agent in 80 percent of UTIs, but other enteric bacteria
from feces can also cause such infections.
When Chlamydia
or Ureaplasma are responsible for infection, they usually are
sexually transmitted and cause nongonococcal urethritis (NGU).
Chlamydia-infection
Prostatitis-(inflammation of the prostate gland). The symptoms of prostatitis are
urgent and frequent urination, low fever, back pain and sometimes muscle and joint
pain. E. coli is the cause of 80 percent of the cases.
Pyelonephritis- an inflammation of the kidney, is usually caused by the backup of
urine and consequent ascent of microorganisms. E. coli causes 90 percent of
outpatient cases and 36 percent of those in hospitalized patients
Glomerulonephritis- or Bright’s disease, causes inflammation and damage to the
glomeruli of the kidney’s. It is an immune complex disease that sometimes follows a
streptococcoal or viral infection
Toxic shock syndrome (TSS)-Infection with certain toxigenic strains of Staphylococcus auerus
can produce TSS.
Sexually Transmitted Disease (STDs)
Bacterial sexually transmitted diseases
Gonorrhea-The causative agent, Neisseria is a Gram-negative spherical or oval diplococcus with
flattened adjacent sides and resembles a pair of coffee beans facing each other.
Figure 20-9 Diplococci of Neisseria gonorrhoeae.
.
Gonococci produce an endotoxin that damages the mucosa in fallopian tubes and releases enzymes such
as proteases and phospholipases that may be important in pathogenesis. They also produce an extracellular
protease that cleaves IgA,. The disease- humans are the only natural hosts for gonococci. Gonorrhea
is transmitted by carriers who either have no symptoms or have ignored them. As many as 40 percent of
males and 60-80 percent of females remain asymptomatic after infection and can act as carriers for 5 to
15 years. High morbidity (about one-third of males become infected after a single sexual exposure) and
95% have pus dripping from the urethra within 14 days.
As many as half of infected females develop pelvic inflammatory disease (PID), in which the
infection spreads throughout the pelvic cavity. Studies done in Sweden showed that sterility often follows
PID because of tubal occlusion by scarring.
Disseminated infections, which occur in1 to 3 percent of cases, produce bacteremia, fever, joint pain,
endocarditis and skin lesions. Gonococcal arthritis is now the most common joint infection in
people 16 to 50 years old. Newborns can acquired ophthalmia neonatorum during passage through the
birth canal of an infected mother.
Within the cytoplasm of
A leukocyte in a urethral smear
Transmission electron microscopy (TEM)
of N. gonorrhoeae
Fig. 20.9 Diplococci of Neisseria gonorrhoeae
From your text:
Syphilis- is caused by he spirochete Treponema pallidum. In the U.S. syphilis is much less
common than gonorrhea. However, the incidence of syphilis has, on average, been on the rise
since 1960, although it has been declining steadily since 1990.
Figure 20-13-Primary chancres of
syphilis
Primary syphilis: an inflammatory response at the
original entry site causes formation of a chancre , a
hard, painless nondischarging lesion about ½ inch in
diameter.
Figure 20-14, Signs of secondary and
tertiary syphilis
This type of wasting
destruction can occur in the
brain or cardiovascular
system
Secondary syphilis: symptoms appear,
disappear, and reappear over a period of
about 5 years, during which the patient
is contagious. These symptoms include
a copper-colored rash, particularly on
the palms of the hands and the soles of
the feet.
Tertiary stage: Permanent damage occurs through various systems of
the body. A wide assortment of symptoms appear including possible
destruction of the brain and cardiovascular system.
Congenital syphilis occurs when the organism crosses the
placenta from mother to baby. At birth or shortly thereafter, the
infant shows a constellation of signs.
Nongonococcal urethritis (NGU)- is a gonorrhea-like STD caused by organism
other than gonococci. Most cases are caused by Chlamydia trachomatis, but some are
caused by mycoplasmas.
The prevalence of chlamydial infections is greater than that
of any other STDs and is increasing dramatically.
Chlamydial infections.- Chlamydia trachomatis is a tiny spherical bacterium with a
complex intracellular life cycle. Pelvic inflammatory disease , is a common
complication of NGU as well as of gonorrhea. Surveys of pregnant women reveal that 11 percent
have Chlamydia in the cervix.
Chlamydia infection of the eye is the most common cause of preventable
blindness in the world.
Mycoplasmal infections- NGU also can be caused by Mycoplasma hominis which is
frequently among the normal urogenital microflora especially in women.
Another causative agent of NGU is Ureaplasma
urealyticum. Between 1
and 2.5 million people in the U.S. are infected. This organism accounts for
more than half of all infections that make couples infertile. Low sperm
count and poor sperm mobility have been observed in males: the organisms bind tightly to
sperm and can be transmitted by them to sexual partners.
Ureaplasma urealyticum is a major cause of fetal death, recurrent miscarriage,
prematurity and low birth weight.
Fig. 20.17 Chlamydia infection rates (per 100,000 population) by sex, in the United States, 1984-2005.
Viral sexually transmitted diseases
Herpes (HSV) infections- HSV-1 typically causes fever blisters (90% HSV1; 10% HSV2), whereas HSV-2
typically causes genital herpes (85% HSV2; 15% HSV1). Oral-genital contact from a person that has HSV 1
can result in genital infection which does not differ from that of HSV2. The opposite is also true
(transmission of HSV 2 to oral cavity)
r. Women infected with genital herpes may be subject to 3 other serious problems: 1) increased risk of
miscarriage, 2) delivery should be by Caesarean section and 3) infected women are at slightly higher
risk for cervical cancer.
Neonatal herpes- can appear at birth or up to 3 weeks after birth.
Gingivostomatitis- lesion of the mucous membranes of the mouth, most common in children 1 to 3 years
old. The most serious manifestation of HSV infection is herpes meningoencephalitis, which can follow a
generalized herpes infection in a newborn, child, or adult. In this disease the activated virus (present in the
trigeminal nerve, which supplies parts of the face and mouth) ascends along the nerve into the brain instead
of moving toward to epithelial sites such as tongue or lips.
Genital warts- Condylomas or genital warts, caused by the human papillomavirus. The
incidence of genital warts has increased rapidly in recent years to the extent that such
warts are now among the most prevalent STDs.
A special hazard of genital warts is their epidemiologic association with
cervical carcinoma. Two strains of human papillomavirus, HPV-8 and HPV-16, are
most likely to be found in cervical carcinomas.
Genital warts are very contagious. You can get them during oral, vaginal, or anal sex with an infected
partner. You can also get them by skin-to-skin contact during vaginal, anal, or (rarely) oral sex with
someone who is infected. About two-thirds of people who have sexual contact with a partner
with genital warts will develop warts, usually within 3 months of contact. Like many STIs,
genital HPV infections often do not have signs and symptoms that can be seen or felt. One
study sponsored by the National Institute of Allergy and Infectious Diseases (NIAID) reported that almost
half of women infected with HPV had no obvious symptoms. If you are infected but have no symptoms,
you can still spread HPV to your sexual partner and/or develop complications from the virus.
Cytomegalovirus (CMVs)- The majority of human CMV infections occur in
older children and adults and go unnoticed because they do not produce clinically
apparent symptoms.
Fetal and infant CMV infections- In fetuses and infants, CMV
infections can be life threatening because the virus disseminates widely to
various organs. Fetuses become infected by viruses that cross the placenta
from infected mothers. In severe CMV infections in which the fetus has been
infected with large numbers of viruses intrauterine growth retardation and severe
brain damage can occur. Many babies have CMV-infected cells in the inner ear
and hearing loss due to nerve damage.
Disseminated CMV. In severe disseminated disease, the virus can be present in
many organs. When the kidneys become infected, immune complexes are
deposited in the glomeruli, but renal dysfunction is rare except in renal transplants.
A baby with severe birth defects due
to Cytomegalovirus