4. Syphilis/Lues.
• T.Pallidum is a delicate spiral bacterium that measures 6-20micrometre in
length and 0.1-0.18 in width. Because of this narrow width, it is not visible
by normal light microscopy and must be visualized by darkfield microscopy
or by silver stains( ie warthin starry or modified Steiners). The organism
reproduces by transverse fission.
Epidemiology studies show that chances are 1/3 of one getting syphilis on
having sexual intercourse with an infected person. It is believed that the
treponemes cannot penetrate intact epidermis or mucosa and that most
infections occur in microscopic and macroscopic breaks in the skin.
• Syphilis is most commonly acquired as a STD but may also be acquired
congenitally (transplacental) or rarely by blood transfusion.
• The organism is very fragile and easily killed by heat, cold, drying ,
disinfectants. Since the organism is very fragile, the possibility that an
infection could be acquired from a toilet seat is statistically very remote.
5. Primary syphilis.
• 3-4weeks after infection
• Primary ulcer: 3-15mm, hard
and initially painless.
• Sometimes instead the syphilitis
lesion maybe papular or crusted
and mimic a balanitis.
• Enlarged regional lymphnodes
• Spontaneous healing of primary
chanre in 6weeks.
6. Diagnosis of Primary syphilis
• Darkfield microscopy.
• Specimen: exudates/fluid from primary chancre, lymphnode aspirate.
7. Secondary syphilis
• 1.5-2months after initial infection
• Condylomata lata.
• Syphilitis roseola
• Mucus patches (asymptomatic erosive patches on the mucus membranes
of oral cavity or genitals).
• Palmoplantar syphilid
• Constitutional symptoms (fever, malaise, headache)
• Lymphadenopathy
• Hepatospleenomegaly
• Diffuse moth eaten alopecia
10. Diagnosis of secondary syphilis…
• Serological tests: Helpful in secondary and probably tertiary stages
Specific: TPHA
Nonspecific: RPR, VDRL
11. Advantages of nonspecific tests.
These tests are positive in some cases of primary syphilis and are
almost always positive in secondary syphilis
The titre of these non specific antibodies decreases with effective
treatment.
The tests is inexpensive and easy to perform. Therefore are used as a
method of screening the population for infection.
NOTE:
• Results of non specific tests usually became negative after treatment
and should be used to determine the response to treatment.
12. Disadvantages of nonspecific tests.
False positive reactions occur in infections such as Leprosy, Hepatitis
B and Infectious mononucleosis and in various autoimmune diseases.
False negative reaction; This is a result of prozone phenomenon.
Early in primary syphilis
Late in tertiary syphilis
13. Specific serological tests.
This tests involve the use of treponemol antigens.
It is more specific than those described above.
This include:-
• Immunofluorescence (FTA-ABS) assay
• Hemagglutination (TPHA, MHA-TP,TP-PA) assay
• Treponemol Enzyme linked immunosorbent assay (ELISA)
• HOW IT WORKS???
• T. pllidum reacts in immunofluorescence(FTA-ABS) or
hemagglutination (TPHA, MHA-TP) assays with specific
treponemal antibodies in the patient’s serum.
14. Specific tests: disadvantages.
• These tests remaining positive for life after effective treatment.
• Can not be used to determine the response to treatment or
reinfection.
• They are more expensive and more difficult to perform.
• They are not used as screening procedures.
15. Late/ tertiary syphilis
• 4-40years after the infection. Cardiovascular and neurological
symptoms predominate
• Gummas. Nodular lesions which cause the skin to break down and
form punched out necrotic ulcers. (painless).
• Skeletal system: periostitis, osteitis and osteomyelitis
• Eye lesions: iritis, choreoretinitis and may result in visual impairment
• Cardiovascular: asymptomatic aortitis, which lead to dilatation of
ascending aorta and eventually to calcification.
16. Neurosyphilis
• Asymptomatic neurosyphilis: describes positive CSF
serology without signs
• Meningovascular syphilis: causes subacute meningitis
with cranial nerve palsies and papilloedema. A
gumma as a localized expanding mass can cause
epilepsy, raised intracranial pressure and focal signs
eg hemiparesis
17. Neurosyphilis cont…
• Tabes Dorsalis: syndrome due to demyelination in the dorsal roots.
• Patients have; lightening pains in the legs, ataxia, neuropathic (
charcot joints), ptosis, optic atrophy, Argyl-robertson pupils
• General Paresis of the insane: there is madness n weakness,
dementia, progressive cognitive decline, brisk reflexes, extensor
plantars. Death occurs in 3 years of onset
18. Congenital syphilis
• Early congenital syphilis develops before age of two years. Typically child is
underweight pale and shrunken
• Other features: Bullous lesions on palms and soles; with paronychia;
snuffles- mucus patches producing a purulent or hemorrhagic discharge;
maculopapular or pustular lesions, condylomata lata, infantile alopecia.
• Osteochondritis of the long bones may cause ‘syphilitis pseudoparalysis’ or
later osteoperiostitis of the proximal phalanges may lead to syphilitis
dactylitis
19. Prevention of congenital syphilis
• Treating primary and secondary syphilis and active case detection
through contact tracing
• Follow up and treatment of VDRL positive blood donors
• Apart from the routine antenatal RPR screening women, high-risk
women should be rescreened in the third trimester of pregnancy thus
preventing reinfection in the later part of pregnancy
20. Chancroid
• Haemophilus ducreyi
• IP: 4-10 days
• A papule or pustule occurs, rapidly
breaks down into multiple, large,
soft and purulent ulcers.
• Men: coronal sulcus or penile shaft
• Women: labia
• Enlarged inguinal lymphnodes-
Buboes
22. Chancroid treatment.
• Ulcerated lesions should be kept clean. Fluctuant lymphnodes should
be aspirated
• Ciprofloxacin 500mg bid for 3days or
• Azithromycin Ig stat. Then 500mg/d for 6days or
• Erythromycin 500mg qid for 14days
24. CHLAMYDIA TRACHOMATIS.
• Causes non gonococcal urethritis.
• L1, L2, L3 serovariants cause lymphogranuoma venereum… Inguinal
Buboes.
• Chlamydia are obligate intracellular bacteriae
• Cell wall similar to those of gram negative bacteria but lack muramic
acid
• Can be grown in cell cultures treated with cycloheximide which inhibit
host cell but not chlamydial protein synthesis
25. Laboratory diagnosis: chlamydia
• Specimen: Exudates
• Test : Giemsa stain
• Findings: Blue mauve stained mass consisting of closely packed
reticulate bodies or less dense mass consisting of mauver-red staining
elementary particles will be seen.
• Other tests: chlamydial antigens can also be detected by ELISA in
exudates or urine. Chlamydia NAAT (nucleic acid amplification
testing). Use first catch urine.
26.
27. GONORHOEA
Gonorrhoea is caused by infection with Neisseria gonorrhoeae.
These organisms infect columnar epithelium in the lower
Genital tract
Rectum.
Pharynx.
Eyes.
NOTE The incubation period in men with gonnococal urethritis is 2 – 10
days
28. Characteristics of Neisseria gonorrhoea.
In Gram stain: they are Gram negative intracellular diplococci that
resemble paired kidney beans.
They contain endotoxin in their outer membrane.
The growth is inhibited by toxic trace metals and fatty acids found in
certain culture media, eg blood agar plates.
They grow in chocolate agar containing blood heated to 80 degree
Celsius, which inactivates the inhibitors.
They are Oxidase –positive.
They cause disease only in human.
29. Laboratory diagnosis.
Laboratory diagnosis depends on:
Gram stain
Culture
Serological test
Specimens from mucosal sites:-
• Urethral discharge
• Vaginal/cervical discharge
• HVS
Note:- For male: patient should not urinate for 2hours
before the specimen is collected.
30. Culture:
• Medium used: Thayer-Martin medium (chocolate
agar containing antibiotics , vancomycin, colistin ,
trimethroprin and nystatin)
INTERPRETATION
Colony appearance:-
• They are tiny greyish colonies.
Biochemical test:-
• They are oxidase +ve
31. Donovanosis
• Klebsiella granulomatis.
• IP; 3-6weeks.
• Initial lesion is a small, non
painful papule, that breaks down
to form large, raised beefy red
ulcers that become painful when
secondarily infected.
• Not accompanied by
lymphadenopathy.
T.Pallidum is a delicate spiral bacterium that measures 6-20micrometre in length and 0.1-0.18 in width. Because of this narrow width, it is not visible by normal light microscopy and must be visualized by darkfield microscopy or by silver stains( ie warthin starry or modified Steiners). The organism reproduces by transverse fission. Syphilis has a myriad of presentations and can mimic many other infections and immune mediated processes in advanced stages.. Hence earned the nickname ‘’ the great imposter’’. The complex and variable clinical presentation prompted sir william osler to remark ‘’ the physician who knows syphilis knows medicine’’
Has not been grown on bacteriological media or in a cell culture but rabbit testicles can be inoculated with the organism which result infection in skin, eyes and testis.
They are spiral rods, thin walled, flexible motile
They are seen only by dark field microscopy, silver impregnation, or immunofluorescence.
Epidemiology studies show that chances are 1/3 of one getting syphilis on having sexual intercourse with an infected person. It is believed that the treponemes cannot penetrate intact epidermis or mucosa and that most infections occur in microscopic and macroscopic breaks in the skin.
Syphilis is most commonly acquired as a STD but may also be acquired congenitally or rarely by blood transfusion.
The organism is very fragile and easily killed by heat, cold, drying , disinfectants. Since the organism is very fragile, the possibility that an infection could be acquired from a toilet seat is statistically very remote.
If untreated, the infection with syphilis goes through four stages.. Primary, secondary, latent and tertiary. Syphilis is caused by the spirochaete Treponema pallidum ssp pallidum. Which belongs to the order spirochaetales. T.pallidum ssp endemicum is a subspecies that causes bejel, or endemic syphilis. T.pallidum ssp pertenue causes yaws and t. carateum causes pinta. There are also other treponema species that infect other animals or are free living
The origin od syphilis is controversial. An epidemic of syphilis ravaged Europe in the last decade of the 15th century, when it was refered to as ‘’the great pox’’ as opposed to small pox. Because this epidemic coincided with the return of Columbus from America in 1493, many authorities believe it was imported from the west Indies(Carribean Basin in America). Of interest , Columbus himself is thought to have died from Syphilitic aortitis. The alternative theory is that syphilis was already endemic in the old world (Europe) but was spread more rapidly during the wars that occurred shortly after the return of columbus
Syphilis serology in the secondary stage is positive. Initial presentation is with syphiloderm (syphilitic roseola, palmoplantar syphilid, mucus patches) and associated systemic symptoms of fever, headache.. Mucus patches are shallow, usually painless erosions of the mucus memranes. Some mucus patches demonstrate linear shapes and have been described as resembling ‘’snailtracks’’
Syphilitis roseola and alopecia. The hairloss presents as a nonscarring, patchy alopecia that is described as ‘’moth-eaten’’ pattern. This classic pattern is uncommon this days, the most common pattern of hairloss in secondary syphilis today is a diffuse hairloss due to telogen effluvium
The nonspecific serologic tests involve use of non treponenal antigens. Extracts from normal mammalian tisue eg ( cardiolipin from beef heart) can react with antibodies in the serum of patients with syphilis. These antibodies are a mixture of IgG and IgM and are called ‘’ reagin ‘’ antibodies.RPR AND VDRL tests look for these antibodies. The non treponemal test measure levels of IgM and IgG produced by the host in response to lipoidal material (mostly cardiolipin) released from damaged host cells. It is also generally believed some cardiolipin is released by spirochaetes as well.
Non treponemal antibodies disappear in an adequately treated person after about 3 years. The titres do reduce and can be used to monitor response to treatment
The prozone phenomenon is a false negative test resulting from high antibody titres which interferes with formation of anigen-antibody lattice, necessary to
visualize a positive flocculation test.
The FTA-ABS , fluorescent treponemal antibody absorption asay positivity on CSF sample or positive VDRL in csf tells us of neurosyphilis. A negative CSF FTA-ABS,,,rules out likelihood for CNS ysphilis
The characteristic lesion of tertiary syphilis, the gumma (granulomatous, sometimes ulcerating lesions) can occur anywhere in the skin, frequently at sites of trauma. Gummas are frequently found in the skull, tibia, fibula, clavicle, although any bone can be involved. Visceral gummas occur mainly in the liver (hepar lobatum) and the testes. Cardiovascular syphilis gives rise to: asymptomatic aortitis, aortic aneurysms usually in the ascending part, aortic valvulitis with regurgitation
Argyl-robertson pupils.. A pupil that doesn’t react to light but constricts to accomodation. Charcot joint refers to progressive degeneration of a weight bearing joint, a process marked by bony destruction, bone resorption and eventual deformity…the commonest cause currently is diabetes but other causes of autonomic n peripheral neuropathy can do the sme eg leprosy, poliomyelitis, spinal cord injury, multiple sclerosis
The ulcers maybe complicated by tissue destruction, phimosis and paraphimosis. The lesions are typically painful. The inguinal lymphnodes may become enlarged, painful and progress to bubo formation. Untreated Buboes may spontaneously rupture and discharge frank pus
Giema staining! Specimen is put on a glass slide, air dried and fixed with methanol. It is then placed in a giemsa stain. Microscopy. Many epithelial cells, polymormonuclear and mononuclear cells ; and chlamydial inclusion bodies can be observed in the cytoplasm of epithelial cells.
Transmission is through genital, anal and oral sex.
The oxidase test is used to identify bacteria that produce cytochrome c oxidase, an enzyme of the bacterial electron transport chain. ( all bacteria that are oxidase positive are aerobic and can use oxygen as a terminal electron acceptor in respiration)
NOTE:
In men, the finding of Gram negative diplococci within PMNs in a urethral discharge specimen is sufficient for diagnosis.
In women, the use of the Gram stain alone can be difficult to interpret;
Gram stain on cervical specimens can be false positive because of the presence of Gram negative diplococci in the normal flora and can be false negative because of inability to see small number of gonococci when using the oil immersion lens. ( moraxella spp)
Moraxella are gram negative organisms that colonize mucosal surfaces.
Diagnosis in female start with Gram stain followed by culture.
Donovanosis is a chronic slowly progressing ulcerative disease involving the skin, mucus membranes and lymphatics of the genitalia and perianal area. The Ulcers bleed to touch and are not accompanied by lymphadenopathy. Common sites are the prepuce, coronl sulcus, and shaft of the penis in men and the vulva and perianal area in women. Extra genital lesions develop through auto inoculation
Donovan bodies! In donovanosis ( granuloma inguinale). Donovan bodies are intracellular inclusions inside macrophages.or just say clusters of encapsulated bacilli in the cytoplasm of mononuclear cells. These aggregates are called donovan bodies and are considered diagnostic
