<< Chapter < Page Chapter >> Page >

Neurosyphilis cannot be diagnosed using a single test. With or without clinical signs, it is generally necessary to assess a variety of factors, including reactive serologic test results, cerebrospinal fluid cell count abnormalities, cerebrospinal fluid protein abnormalities, or reactive VDRL-CSF (the VDRL test of cerebrospinal fluid). The VDRL-CSF is highly specific, but not sufficiently sensitive for conclusive diagnosis.

The recommended treatment for syphilis is parenteral penicillin G (especially long-acting benzathine penicillin, although the exact choice depends on the stage of disease). Other options include tetracycline and doxycycline .

a) micrograph of a spiral cell. b) micrograph of many spiral cells.
(a) Darkfield micrograph of Treponema pallidum. (b) Silver stain micrograph of the same species. (credit a, b: modification of work by Centers for Disease Control and Prevention)

Congenital syphilis

Congenital syphilis is passed by mother to fetus when untreated primary or secondary syphilis is present. In many cases, infection may lead to miscarriage or stillbirth. Children born with congenital syphilis show symptoms of secondary syphilis and may develop mucus patches that deform the nose. In infants, gummas can cause significant tissue damage to organs and teeth. Many other complications may develop, such as osteochondritis , anemia , blindness, bone deformations, neurosyphilis, and cardiovascular lesions. Because congenital syphilis poses such a risk to the fetus, expectant mothers are screened for syphilis infection during the first trimester of pregnancy as part of the TORCH panel of prenatal tests.

  • What aspect of tertiary syphilis can lead to death?
  • How do treponemal serologic tests detect an infection?

Chancroid

The sexually transmitted infection chancroid is caused by the gram-negative rod Haemophilus ducreyi . It is characterized by soft chancres ( [link] ) on the genitals or other areas associated with sexual contact, such as the mouth and anus. Unlike the hard chancres associated with syphilis, soft chancres develop into painful, open sores that may bleed or produce fluid that is highly contagious. In addition to causing chancres, the bacteria can invade the lymph nodes, potentially leading to pus discharge through the skin from lymph nodes in the groin. Like other genital lesions, soft chancres are of particular concern because they compromise the protective barriers of the skin or mucous membranes, making individuals more susceptible to HIV and other sexually transmitted diseases.

Several virulence factors have been associated with H. ducreyi , including lipooligosaccharide s, protective outer membrane proteins, antiphagocytic proteins , secretory proteins, and collagen-specific adhesin NcaA . The collagen-specific adhesion NcaA plays an important role in initial cellular attachment and colonization. Outer membrane proteins DsrA and DltA have been shown to provide protection from serum-mediated killing by antibodies and complement.

H. ducreyi is difficult to culture; thus, diagnosis is generally based on clinical observation of genital ulcers and tests that rule out other diseases with similar ulcers, such as syphilis and genital herpes. PCR tests for H. ducreyi have been developed in some laboratories, but as of 2015 none had been cleared by the US Food and Drug Administration (FDA). Centers for Disease Control and Prevention. “2015 Sexually Transmitted Diseases Treatment Guidelines: Chancroid,” 2015. http://www.cdc.gov/std/tg2015/chancroid.htm. Recommended treatments for chancroid include antibiotics such as azithromycin , ciprofloxacin , erythromycin and ceftriaxone . Resistance to ciprofloxacin and erythromycin has been reported. Ibid.

a) Photo of a white swelling on a penis. B) micrograph of rod shaped pink cells.
(a) A soft chancre on the penis of a man with chancroid. (b) Chancroid is caused by the gram-negative bacterium Haemophilus ducreyi , seen here in a gram-stained culture of rabbit blood. (credit a, b: modification of work by Centers for Disease Control and Prevention)
  • What is the key difference between chancroid lesions and those associated with syphilis?
  • Why is it difficult to definitively diagnose chancroid?

Bacterial reproductive tract infections

Many bacterial infections affecting the reproductive system are transmitted through sexual contact, but some can be transmitted by other means. In the United States, gonorrhea and chlamydia are common illnesses with incidences of about 350,000 and 1.44 million, respectively, in 2014. Syphilis is a rarer disease with an incidence of 20,000 in 2014. Chancroid is exceedingly rare in the United States with only six cases in 2014 and a median of 10 cases per year for the years 2010–2014. Centers for Disease Control and Prevention. “2014 Sexually Transmitted Disease Surveillance,” 2015. http://www.cdc.gov/std/stats14/default.htm. [link] summarizes bacterial infections of the reproductive tract.

Table title: Bacterial Infections of the Reproductive Tract. Columns: Disease, Pathogen, Signs and Symptoms Transmission, Diagnostic Tests, Antimicrobial Drugs. Disease - Bacterial vaginosis (BV); Gardnerella vaginalis, Bacteroides spp., Fusobacterium spp., others; Often asymptomatic; vaginal discharge, burning, odor, or itching Opportunistic infection caused by imbalance of normal vaginal microbiota; Vaginal smear; Clindamycin, metronidazole, tinidazole. Disease – Chancroid; Haemophilus ducreyi; Soft, painful chancres on genitals, mouth, or anus; swollen lymph nodes; pus discharge; Sexual contact or contact with open lesions or discharge; Observation of clinical symptoms and negative tests for syphilis and herpes; Azithromycin, ceftriaxone, erythromycin, ciprofloxacin. Disease - Chlamydia ; Chlamydia trachomatis; Often asymptomatic; in men, urethritis, epididymitis, orchitis; in women, urethritis, vaginal discharge or bleeding, pelvic inflammatory disease, salpingitis, increased risk of cervical cancer ; Sexual contact or from mother to neonate during birth; NAAT, urine sample, vaginal swab, culture; Azithromycin, doxycycline, erythromycin, ofloxacin, or levofloxacin. Disease – Gonorrhea; Neisseria gonorrhoeae; Urethritis, dysuria, penile or vaginal discharge, rectal pain and bleeding; in females, pelvic pain, intermenstrual bleeding, pelvic inflammatory disease, salpingitis, increased risk of infertility or ectopic pregnancy; in disseminated infections, arthritis, endocarditis, meningitis; Sexual contact ; Urine sample or culture, NAAT, PCR, ELISA; Ceftriaxone, azithromycin. Syphilis; Treponema pallidum Primary: hard chancre; Secondary: rash, cutaneous lesions, condylomata, malaise, fever, swollen lymph nodes; Tertiary: gummas, cardiovascular syphilis, neurosyphilis, possibly fatal; Sexual contact or from mother to neonate during birth; Darkfield or brightfield silver stain examination of lesion tissue or exudate, treponemal and non-treponemal serological testing, VDRL-CSF for neurosyphilis, prenatal TORCH panel; Penicillin G, tetracycline, doxycycline.

Key concepts and summary

  • Bacterial vaginosis is caused by an imbalance in the vaginal microbiota, with a decrease in lactobacilli and an increase in vaginal pH. G. vaginalis is the most common cause of bacterial vaginosis, which is associated with vaginal discharge, odor, burning, and itching.
  • Gonorrhea is caused by N. gonorrhoeae , which can cause infection of the reproductive and urinary tracts and is associated with symptoms of urethritis. If left untreated, it can progress to epididymitis, salpingitis, and pelvic inflammatory disease and enter the bloodstream to infect other sites in the body.
  • Chlamydia is the most commonly reported STI and is caused by C. trachomatis . Most infections are asymptomatic, and infections that are not treated can spread to involve the epididymis of men and cause salpingitis and pelvic inflammatory disease in women.
  • Syphilis is caused by T. pallidum and has three stages, primary, secondary, and tertiary. Primary syphilis is associated with a painless hard chancre lesion on genitalia. Secondary syphilis is associated with skin and mucous membrane lesions. Tertiary syphilis is the most serious and life-threatening, and can involve serious nervous system damage.
  • Chancroid is an infection of the reproductive tract caused by H. ducreyi that results in the development of characteristic soft chancres .

Fill in the blank

Soft chancres on the genitals are characteristic of the sexually transmitted disease known as _____.

chancroid

Got questions? Get instant answers now!

Short answer

Compare gonococcal and nongonoccocal urethritis with respect to their symptoms and the pathogens that cause each disease.

Got questions? Get instant answers now!

Questions & Answers

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
tijani
what is titration
John Reply
what is physics
Siyaka Reply
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
Jude
what is the dimension formula of energy?
David Reply
what is viscosity?
David
what is inorganic
emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
Krampah Reply
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
Sahid Reply
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
Samuel Reply
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
Ryan
what's motion
Maurice Reply
what are the types of wave
Maurice
answer
Magreth
progressive wave
Magreth
hello friend how are you
Muhammad Reply
fine, how about you?
Mohammed
hi
Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
yasuo Reply
Who can show me the full solution in this problem?
Reofrir Reply
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Microbiology' conversation and receive update notifications?

Ask