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Chapter: Medicine Study Notes : Reproductive and Obstetrics

Sexually Transmitted Diseases (STDs)

Types and incubation: o Chlamydia (7 –21 days) -> don‟t test till 14 days after contact (unless symptomatic) o Gonorrhoea (range 1 – 14 days, commonly 2 – 5 days) o Trichomonas (3 – 21 days)

Sexually Transmitted Diseases (STDs)


·        Types and incubation: 

o  Chlamydia (7 –21 days) Þ don‟t test till 14 days after contact (unless symptomatic)

o  Gonorrhoea (range 1 – 14 days, commonly 2 – 5 days)

o  Trichomonas (3 – 21 days)

o  Herpes Simplex Virus (2 days onwards – maybe years)

o  Human Papilloma Virus (2 – 4 months, up to a year, vertical transmission possible) 

o  Human Immunodeficiency Virus (HIV) – (seroconversion illness 2 – 6 weeks after exposure, HIV antibodies almost always present after 3 months. Mean time to developing AIDS defining illness 9        12 years)

o  Hepatitis B (1 – 6 months)

o  Syphilis (9 – 90 days)

o  Non-specific urethritis

o  Pubic Lice (eggs – 2 weeks to mature, larvae – 1 week to mature)

o  Scabies (3 – 30 days, 6 weeks for itch to develop)

o  Hepatitis C and A may be sexually transmitted

·        Not necessarily sexually transmitted:

o  Normal anatomical variants

o  Commensals ® bacterial vaginosis

o  Dermatoses

o  Candidacies (commensals)

o  Molluscum contagiousum (3 weeks – months)

o  Urinary tract infections

o  Prostatitis

o  Vulval disorders

Tests for STD’s


·        Urethral swab or first pass urine for chlamydia

·        Anal or throat swab for gonorrhoea if appropriate

·        Female:

o   Cervical sample for gonorrhoea, chlamydia (endocervical cells needed)

o   Cervical smear

o   High vaginal swab for bacterial vaginosis, candida, trichomonas

·        Male: Urethral swab for gonorrhoea

·        Blood tests:

o   Hepatitis B (Ag and Ab) and C (Ab)

o   Syphilis: VDRL, TPHA

o   HIV Ab if appropriate with counselling and consent.  Always attend for results


Vaginal Discharge


·        Cervical secretions in women not on the pill, and which change during the cycle, are part of normal discharge. Mucus is clear or clear/white. Some inflammatory cells are normal in the latter half of a cycle


·        Desquamating vaginal cells with healthy lactobacilli are major part of normal discharge – pH < 4.5

·        Key history questions:

o   Colour

o   Odour

o   Itch

·        Differential:

o   Thrush (Candidiasis): white curds, very itchy, not smelly

o   Trichomoniasis: grey/green discharge, fishy smell, moderate itch

o   Bacterial Vaginosis: green, fishy, itchy

o   Chlamydia: asymptomatic or discharge 

o   Atrophic vaginitis: brown, spotty discharge (from bruising), pain, no itch. Treatment: oestrogen cream or HRT



Neisseria Gonorrhoeae


·        Description:  G –ive diplococci

·        Symptoms:

o  Male: 80% symptomatic.  Discharge & dysuria (razor blade pain).  30% also have chlamydia 

o  Female: only 20% symptomatic – can have vaginal discharge or pelvic pain. Pick up with opportunistic/selective screening if under 25, multiple partners, changed partner in last 6 months, IUCD, etc 

o  Rectal and pharyngeal: often asymptomatic

·        Diagnosis: gram stain microscopy if symptomatic or contact, or culture on chocolate agar

·        Advice: no sex until minimum of 3 days since treatment completed

·        Treatment: 

o  Amoxycillin 3 gm and Probenecid 1 gm stat (not longer standard due to ­ penicillin resistant), or 

o  Ciprofloxacin 500 mgs (a quinolone) stat if penicillin allergy or if resistant. Specialist endorsement required. If resistant to that then Ceftriaxone (common in Auckland). 

o  Azithromycin will cover gonorrhoea if it is being used to treat concurrent chlamydia

o  Resistance possible

·        Contact tracing required. Treat partners

·        Test for cure at 14 days (legal requirement)

·        Complications: See Topic: Pelvic Inflammatory Disease (PID)


Chlamydia Trachomatis


·        Description: obligate intracellular bacteria, STIs are types D – K.  Highest in 20 – 24 year age group

·        Symptoms:

o  Urethritis, unexplained cystitis, mucopurulent cervicitis, pelvic pain, irregular bleeding 

o  80% of females and 50% of males have no symptoms. Suspect and test if sexual contacts have it, if patients asks for STI tests, patients under 25 with new/multiple partners

o  Up to 30% associated with concurrent N Gonorrhoea infection

·        Diagnosis: 

o  Female: swab from affected area, including from endocervix. Rotate 6 – 10 times. Urine test alone not sufficient. Most common site of single infection is cervix (ie urine is clear)

o  Male: urine test

o  New PCR test easier sampling (urine test)

o  Opportunistic detection has been shown to reduce rates of PID and ectopic pregnancy

·        Advice:

o  Abstain until treated – if not use condoms

o  Contact trace

·        Treatment:

o  Without test results: Doxycycline 100mgs bd for 7 days (remember 7 day rule for patients on OC)

o  Known positive and partners: Azithromycin 1 g stat orally – directly observed treatment 

o  In pregnancy: erythromycin ethylsuccinate 800mg qid for 7 days – must be treated to prevent amnionitis and premature rupture of membranes 

o  In PID: Doxycycline/erythromycin for 14 days and ornidazole 500 mgs bd for 7 days, plus consider gonorrhoea in which case penicillin/ciprofloxacin in addition 

o  Test of cure in 3 weeks if non-compliance or re-infection suspected. Urine test is adequate for males and females 

o  Test high risk patients only for cure

o  If reinfection, then ?untreated partner

·        Complications:

o   Neonatal: conjunctivitis, pneumonitis 2 – 4 weeks later

o   See Topic: Pelvic Inflammatory Disease (PID)


Herpes Simplex Virus (Type 2) 


·        Manifestations: systemic (fever, sore throat), gingivostomatitis (ulcers with yellow slough – cold sores), meningitis (uncommon, self-limiting), encephalitis (fever, fits, headache, dysphagia, hemiparesis – do PCR on CSF sample – refer urgently) 

·        Incubation: 2 – 25 days. Chronic infection is due to the virus remaining in the sensory nerve ganglia. Infectious period indeterminate ® contact isolation

·        Symptoms:

o  Blisters which become shallow painful ulcers, often preceded by itching or tingling

o  First episode may be accompanied by flu like illness, tender inguinal nodes and dysuria 

o  Recurrences can be brought on by stress, fatigue, depression, immunosuppression and concurrent illness. Recurrences usually less severe and become less frequent 

·        Diagnosis: clinical suspicion. Swab the base of an unroofed ulcer and refrigerate in viral medium. This will be painful. Culture negative doesn‟t exclude HSV as timing and collection technique important.

·        Serology possible, but not routinely used

·        Pathogenesis.  There are two antigenic types of Herpes Simplex Virus: 

o  Type 1 is associated with lesions on the face and fingers, and sometimes genital lesions. Treat with zovirax (topical cream). Prevalence: 70% of population 

o  Type 2 is associated almost entirely with genital infections, and affects the genitalia, vagina, and cervix and may predispose to cervical dysplasia. 10% of oral lesions caused by type 2. Prevalence: 10 – 15% of population (depends on population – more in high risk) 


Pelvic Inflammatory Disease (PID)


·        ~ Tubulo-peritoneal Disease

·        Cause: ascending infection of vagina and cervix to endometrium, fallopian tubes and other structures:

o   Chlamydia – often chronic

o   Gonorrhoea – often acute

o   Can also be anaerobes (e.g. after instrumentation of the uterus or long standing PID)

·        Symptoms: Acute pain, but 30% asymptomatic, dyspareunia (pain on sex)

·        Risk factors:

o   Young age (< 25) 

o   ­Sexual activity, multiple partners, multiple infections

o   Postpartum infections

o   IUCDs in first several weeks after insertion 

o   Decreased rates with condoms, diaphragms, spermicides (bacteria can use sperm as vector), tubal ligation, OC pill 

·        Diagnosis:

o   Difficult to make clinically: there are multiple causes of abdominal pain

o   Cervical motion tenderness (also occurs with ectopic pregnancy)

o   Purulent cervical/vaginal discharge

o   Oral temperature > 38 C

o   Irregular bleeding and break through bleeding on the OC pill

o   Ultrasound of no help.  Test for other STIs.  May require laproscopy 

·        Treatment: Antibiotics must cover anaerobes, chlamydia and gonorrhoea. E.g. Doxycycline 100 mg bd for 10 – 14 days plus an anti-anaerobe such as metronidazole or ornidazole

·        Sequalae:

o   Often repeat episodes due to:

§  Continued at risk behaviour

§  Partner is not treated

§  Past infection compromises cilia of the fallopian tubes making another infection more likely

o   Infertility risk after 1 infection is 11%, but up to 54% after 3 infections

o   Other sequalae: ectopic pregnancy, adhesions, chronic pelvic pain


Reiter’s Syndrome*


·        Triad of arthritis (big joints – hot, red swollen, bilateral), urethritis and conjunctivitis

·        10:1 are males, usually 25 – 35 years

·        Often (not always) caused by chlamydia (an immunological reaction, HLA B27+ more susceptible)

·        Treatment: treat residual infection, if any


Genital Warts


·        Can get anal warts without anal intercourse

·        External warts usually benign (types 6 & 11 – not oncogenic)

·        Treatment:

o   Destructive: Condyline, liquid nitrogen – high recurrence rate 

o   Imiquimod – topical cream, up-regulates immune system, expensive ($150 per month), 19% recurrence, requires treatment for 8 – 12 weeks

·        A vaccine is at stage 3 trials


Non-Sexually Transmitted Genital Skin Lesions


·        Not all skin lesions on the genitals and surrounding areas are due to STDs

·        Normal anatomical variants:

o   Pearly penile papules: small papillae around the corona of the penis

o   Sebaceous cysts of the penis, labia minora and scrotum

o  Normal papillae in the vaginal vestibule: can be mistaken for warts

·        Dermatoses:

o  Contact dermatitis: soaps, deodorants, etc 

o  Psoriasis: especially head and corona of the penis. Red, scaly plaques. Not itchy. Look for it elsewhere

o  Reiter‟s Syndrome: urethritis, conjunctivitis, arthritis in addition to skin lesion

o  Lichen Planus: itchy plaques on the penis

·        Infections (not necessarily sexually acquired):

o  Seborrhoeic dermatitis: a fungus, red, sharply defined area covered with honey coloured scales

o  Candidiasis: red, irritating, itchy rash.  Treat with Clotrimazole (Canesten)

o  Dermatophyte infections (tinea) are common.  Characteristic spreading edge, itchy

o  Folliculitis: small pustule around a hair follicle

o  Scabies: red, itchy nodules – may not resolve despite treatment.  Treat with malathion 0.5%

o  Erythrasma: scaly, flat, brown, pigmented rash, not itchy.  Caused by corynebacterium 

o  Molluscum contagiosum: may be sexually acquired. Small, pearly umbiliated lesions on the thigh and buttocks




·        The virus: RNA virus with reverse transcriptase.  Has p24 nuclear antigen.  Attacks CD4+ T cells. 

·        Transmission: sex (­risk in receptive intercourse – male to male most significant, also in other STDs), blood and maternal transmission (¯ risk with AZT) 

·        1 % of Europeans lack CXR-5 receptor: if homozygous then resistant

·        Signs & Symptoms:

o   ­Temperature, wasting (chronic ill health) 

o   Rashes: eg shingles, HSV (cold sores), candidiasis, may be drug response (heightened sensitivity to drug responses)

o   Lymph nodes

o   Signs of high risk behaviour: Injection marks, other STD

o   Mouth: infections, Kaposi‟s Sarcoma (re-purple vascular non-tender tumours – mainly on skin)

o   Chronic cough common

o   Hepatosplenomegaly (infections, lymphoma)

o   Neuropathies: eg due to intracranial lesion (eg lymphoma), peripheral sensory neuropathies

o   Fundi: cotton wool spots, scars (eg due to toxoplasmosis, CMV)

·        Early disease:

o   Seroconversion illness: in 50 – 90% of infected people.  May include macular rash

o   Debate about usefulness of early treatment

o   Good evidence of value of prophylactic treatment (e.g. following needle stick)

·        Screening:

o   3 weeks before positive after infection

o   Elisa for HIV-1 and HIV-2 antibodies

o   False positive tests: 4/1000

·        Confirmatory diagnosis: Western Blot

o   Can take up to 3 months to get Western Blot Positive

o   Can give indeterminate, weak positive or strong positive (3 bands)

·        Course: measure based on viral load and CD4 count

o   Acute illness: 4 – 8 weeks

o   Asymptomatic: 2 – 12 years

o   Symptomatic: 2+ years.  AIDS defining illness: 

§  PCP infection (treat with co-trimoxazole): can ® pneumothorax

§  Cryptococcus infection: mild headaches: lumbar puncture.  Indian ink stain positive

§  Kaposi‟s sarcoma: can present anywhere

§  Psychological: HIV related, secondary illness related, or depression

·        Viral Load:

o   High T cell turnover:  Virus replicates in 1½ days.  Infected cell lasts 2.2 days

o   HIV in sanctuary sites: e.g. brain – hard to treat

o   Measure through PCR of viral RNA: good indicator of progression.  If viral load high, treat now

·        Immune depletion: Based on CD4+ count:

o   > 500

o   200 – 500: Tb, herpes

o   <200

·        Subgroups of illness:

o   Constitutional: fever, diarrhoea, weight loss

o   Neurological: dementia, neuropathy, cognitive

o   Opportunistic infections: candida, PCP, toxoplasmosis, CMV, MAC, Tb

o   Malignancies: Kaposi‟s sarcoma, non-Hodgkin‟s lymphoma

·        Drug Treatment:

o   Combination of drugs that inhibit various points of viral replication

o   Can improve CD4+ count from very low (e.g. 50) to e.g. 500-600

o   Side-effects: non-specific rashes, „buffalo hump‟ – abnormal fat distribution

·        Leading cause of death: Respiratory infection


Testing for HIV


·        Guidelines for HIV pre-test counselling:

o   What the test for HIV antibodies means: not a test for AIDS

o   Significance of negative test (Window period)

o   Significance of positive test: medical implications (prognosis & treatment), social implications (coping, support, relationships, who needs to know, possible discrimination), notification requirements (HIV not notifiable, patient can use alias), implications for insurance

o  Safeguards to preserve confidentiality

o  Future preventative aspects: safer sex and IVDU

o  How results are obtained

o  Any costs

·        Guidelines for post test counselling:

o  Explanation of test results

o  If negative: 3-month window period – especially if recent high risk behaviour.  Future prevention 

o  If positive: repeat, confirmatory test organised, arrangement for counselling, support and specialist assessment 

Other Causes of Secondary Immunodeficiency


·        Malignancy

·        Drugs e.g. steroids, cyclosporin, cytotoxics

·        Nutritional Deficiency

·        Post-viral

·        Post-transfusion

·        Alcoholism

·        Chronic renal disease


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