Term
| What are two things unique about spirochetes? |
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Definition
1. Surrounded by an additional phospholipid-rich outer membrane with few exposed proteins (protection from immune recognition)
2. Periplasmic flagella: enable rotation |
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Term
| How to identify spirochetes? |
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Definition
| Darkfield microscopy, immunofluorescence, silver stain. |
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Term
| Can you culture spirochetes? Identify under the light microscope? |
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Definition
* No.
* No, too small for LM. |
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Term
| What are 3 genera for spirochetes? |
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Definition
1. Treponema
2. Borrelia
3. Leptospira |
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Term
| What is the mechanism of pathology for treponemes (a type of spirochetes)? |
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Definition
| Host's own immune response (treponemes do not have known toxins or tissue destructive enzymes) |
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Term
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Definition
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Term
| In primary syphilis, ulcer erupts 3 - 6 weeks after contact, and resolves 4-6 weeks w/o a scar. Do the ulcers cause pain? |
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Definition
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Term
| What happens in secondary syphilis? |
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Definition
| The bacteria spreads in the blood, leading to systemic symptoms (widespread rash, condyloma latum, loss of eyebrows, lymphadenoapthy, weight loss, fever). Appears ~6 weeks after primary chancre has healed, secondary resolves in 6 weeks. |
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Term
| What happens during latent syphilis? |
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Definition
| secondary features are gone. serologic test may be positive. 25% have relapses. not infectious. 1/3 progress into tertiary syphilis. |
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Term
| What are three general categories of tertiary syphilis? |
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Definition
1. Gummatous syphilis
2. Cardiovascular syphilis
3. neurosyphilis |
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Term
| Pathophysiology and location of gummatous syphilis? |
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Definition
* Localized granulomatous lesions which eventually necrose and become fibrotic.
* skin: painless; bone: deep pain |
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Term
| Can you treat gummatous syphilis? |
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Definition
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Term
| What happens in cardiovascular syphilis? |
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Definition
| Chronic inflammatory destruction of vasa vasorum supplying the aorta. Necrosis ofthe media layer of the aorta. Aortic aneurism. Cannot reverse with antimicrobials. |
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Term
| Which two bacteria cause subacute meningitis with a predominance of lymphocytes? |
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Definition
Treponema pallidum
Mycobacterium tuberculosis |
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Term
| A condition of tertiary syphilis, which affects the posterior column and dorsal roots of spinal cord? |
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Definition
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Term
| Symptoms of tabes dorsalis |
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Definition
* posterior column damage: disruption of vibratory and proproceptive sensations --> ataxia
* Dorsal root and ganglia damage --> loss of reflexes, loss of pain and temperature sensations |
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Term
| What is "Argyll-Robertson pupil" which is present in both tabes dorsalis and general paresis? |
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Definition
| Constricts during accommodation but does not react to light. |
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Term
| What are the symptoms for early congenital syphilis (vertical transmission, w/n 2 years) |
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Definition
| Like severe adult secondary syphilis. Mucous membrane involvement: snuffles |
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Term
| Late congenital syphilis symptoms |
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Definition
| Similar to adult tertiary syphilis. Cardiovascular sx are rare. Eight nerve deafness is common. Saddle nose (periosteal inflammation of teeth --> destroied cartilage of palate and nasal septum), saber shins, Hutchinson's teeth (upper central incisors widely spaced with a central notch on each tooth), eye disease |
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Term
| When does the maternal syphilis affect the fetus? |
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Definition
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Term
| Diagnostic tests for syphilis? |
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Definition
* Direct visualization of spirochetes during active stage
* nonspecific treponemal tests
* specific treponemal tests |
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Term
| What are you looking for in nonspecific treponemal tests? |
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Definition
Damaged host cells from treponema palldium release lipids including cardiolipin and lecithin. The body makes antibodies for those lipids. These antibodies can be detectable in the serum/CSF.
* Veneral Disease Research Laboratory (VDRL)
* Rapid Plasma Reagin (RPR)
Nonspecific because 1% of general population is positive |
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Term
| What are specific treponemal tests? |
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Definition
Detecting antibodies against the spirochetes. Indirect Immunofluorescent Treponemal Antibody-Absorption (FTA-ABS) test.
Pt. serum + nonpathological treponema (normal flora) --> Pt. serum + killed T. pallidum |
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Term
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Definition
Penicillin
If allergic, erythromycin and doxycyclin (dox not for fetus).
With Tx, nonspecific Ab decrease, specific Ab remain the same.
T. palldium killed by heat, drying, soap and water. |
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Term
| What is Jarisch-Herxheimer Phenomenon? |
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Definition
Syphilis patients upon antibiotics-treatment develop acute worsening of symptoms: mild fever, chills, malaise, headache, and myalgia.
This is due to released pyrogen. |
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Term
| Do subspecies of Treponema pallidum also cause syphilis? |
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Definition
| Yes, but not STD. Skin ulcers present. 2' stage with widespread lesions. 3' stage with gummas of the skin and bones but w/o heart or CNS symptoms. |
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Term
| What is "endemic syphilis" and what causes it? |
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Definition
| Treponema pallidum Subspecies endemicum causes it. In deserts of Africa and Middle East, by sharing utensils. Oral mucosal ulcers. |
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Term
| What is "endemic syphilis" and what causes it? |
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Definition
| Treponema pallidum Subspecies endemicum causes it. In deserts of Africa and Middle East, by sharing utensils. Oral mucosal ulcers. |
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Term
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Definition
| Disfiguring lesion of the skin, caused by T. palldium Subspecies pertenue, destroying the bone, cartilage, and skin. Yaws. In moist tropical regions. |
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Term
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Definition
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Term
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Definition
| Rural Latin America. By Treponema pallidum Subspecies carateum. Purely skin lesions that turn red, blue with sun, and white (depigmented). |
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Term
| Which vector and primary organism cause Lyme disease? |
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Definition
vector: Ixodes tick
organism: Borrelia burgdorferi (spirochete, gram-) |
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Term
| Which disease causes the painless skin lesion, erythema chronicum migrans? |
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Definition
| Lyme disease. Target shaped. |
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Term
| Lyme disease has three stages. What are the characteristics of early localized stage? |
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Definition
- 10 days after tick bite, lasts for 4 weeks.
- erythema chronicum migrans
- flulike illness
- regional lymphadenopathy |
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Term
| What are the target systems for early disseminated stage of Lyme disease? |
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Definition
1. Skin (erythema chronicum migrans. smaller than primary lesions, and diffuse.)
2. Nervous system (meningitis, CN 7 Bell's palsy, peripheral neuropathies)
3. Heart (AV nodal block, myocarditis, LV dysfunction)
4. Joint and muscle pain |
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Term
| What are the manifestations of late stage Lyme disease? |
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Definition
Chronic arthritis (10% of untreated pt)
Encephalopathy |
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Term
| Which anti-bacterials are used to treat Lyme disease? |
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Definition
| Doxycycline and penicillin family |
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Term
| What causes relapsing fever and how to treat it? |
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Definition
Borrelia recurrentis. Gram- spirochete. Keep changing antigen to escape host antibodies.
Tx: Doxycycline, erythromycin |
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Term
Which organism caused the following clinical picture?
Went swimming in a pool contaminated by dog urine. Abrupt onset of fever, headache, malaise, myalgia (thigh, lower back), conjunctivitis, photophobia. After a week, short afebrile period, then the same symptoms again. |
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Definition
| Leptospira (aerobic spirochete, gram-) |
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Term
| What causes Weil's disease (infectious jaundice, renal failure, hepatitis with jaundice, mental status changes, hemorrhages) |
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Definition
| Leptospira interrogans (spirochete) |
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