Question 51#

You are reviewing test results. The midstream specimen of urine (MSU) from a 24-year-old woman who is 11 weeks pregnant shows a urinary tract infection. On discussing the result with the patient she does describe some dysuria and 'smelly urine'.

What is the most appropriate management?

A. Ciprofloxacin for 7 days

Correct Answer B: As this woman is symptomatic she should be treated with an antibiotic that is safe to use in pregnancy.

Urinary tract infection in adults: management:
Lower urinary tract infections in women (cystitis):

• Local antibiotic guidelines should be followed if available
• Clinical Knowledge Summaries (CKS) recommend trimethoprim or nitrofurantoin for 3 days

Lower urinary tract infections in pregnancy: 

• Asymptomatic bacteriuria is screened for on the booking visit. If found, it should be confirmed with a second MSU and treated if confirmed (please see CKS link for more details)
• For acute lower urinary tract infections consider amoxicillin or an oral cephalosporin for 7 days*

For patients with sign of acute pyelonephritis hospital admission should be considered: 

• Local antibiotic guidelines should be followed if available
• The BNF currently recommends a broad-spectrum cephalosporin or a quinolone for 10-14 days
• Clinical Knowledge Summaries recommend ciprofloxacin for 7 days or co-amoxiclav for 14 days

*CKS also mention the use of trimethoprim and nitrofurantoin. Trimethoprim is a folate antagonist and concerns have been raised regarding the potential risk of neural tube defects. Manufacturers advise to avoid. Whilst short term trimethoprim use is unlikely to cause folate deficiency it would seem reasonable to use an antibiotic such as amoxicillin first-line. Nitrofurantoin should be avoided at term because of the risk of neonatal haemolysis.

Question 52#

A 26-year-old man returns to the genito-urinary medicine clinic. He is a known intravenous drug user. Five days ago he was seen with a urethral discharge. A swab taken in the clinic showed a Gram-negative diplococcus and treatment with IM ceftriaxone was given. Unfortunately his symptoms have not resolved.

What is the most likely explanation?

A. Gonorrhoea-resistant to ceftriaxone

Correct Answer E: Co-existent infection with Chlamydia is extremely common in patients with gonorrhoea.

Chlamydia:

Chlamydia is the most prevalent sexually transmitted infection in the UK and is caused by Chlamydia trachomatis, an obligate intracellular pathogen. Approximately 1 in 10 young women in the UK have Chlamydia. The incubation period is around 7-21 days, although it should be remembered a large percentage of cases are asymptomatic.

Features: 

• Asymptomatic in around 70% of women and 50% of men
• Women: cervicitis (discharge, bleeding), dysuria
• Men: urethral discharge, dysuria 

Potential complications: 

• Epididymitis
• Pelvic inflammatory disease
• Endometritis
• Increased incidence of ectopic pregnancies
• Infertility
• Reactive arthritis
• Perihepatitis (Fitz-Hugh-Curtis syndrome)

Investigation: 

• Traditional cell culture is no longer widely used
• Nuclear acid amplification tests (NAATs) are now rapidly emerging as the investigation of choice
• Urine (first void urine sample), vulvovaginal swab or cervical swab may be tested using the NAAT technique

Screening: 

• In England the National Chlamydia Screening Programme is open to all men and women aged 15- 24 years
• The 2009 SIGN guidelines support this approach, suggesting screening all sexually active patients aged 15-24 years
• Relies heavily on opportunistic testing

Management:

• Doxycycline (7 day course) or azithromycin (single dose). The 2009 SIGN guidelines suggest azithromycin should be used first-line due to potentially poor compliance with a 7 day course of doxycycline
• If pregnant then erythromycin or amoxicillin may be used. The SIGN guidelines suggest considering azithromycin 'following discussion of the balance of benefits and risks with the patient'
• Patients diagnosed with Chlamydia should be offered a choice of provider for initial partner notification - either trained practice nurses with support from GUM, or referral to GUM
• For men with symptomatic infection all partners from the four weeks prior to the onset of symptoms should be contacted
• For women and asymptomatic men all partners from the last six months or the most recent sexual partner should be contacted
• Contacts of confirmed Chlamydia cases should be offered treatment prior to the results of their investigations being known (treat then test)

Question 53#

A pregnant 34-year-old female presents with uncomplicated Falciparum malaria following a trip to Kenya.

Which one of the following is the most suitable treatment?

A. Chloroquine

Correct Answer D: Both artemether and atovaquone are not currently recommended in pregnancy.

Malaria: Falciparum:

Feature of severe malaria: 

• Schizonts on a blood film
• Parasitaemia > 2%
• Hypoglycaemia
• Temperature > 39 °C
• Severe anaemia
• Complications as below

Complications:

• Cerebral malaria: seizures, coma
• Acute renal failure: blackwater fever, secondary to intravascular haemolysis, mechanism unknown
• Acute respiratory distress syndrome (ARDS)
• Hypoglycaemia
• Disseminated intravascular coagulation (DIC)

Uncomplicated falciparum malaria: 

• Strains resistant to chloroquine are prevalent in certain areas of Asia and Africa
• The 2010 WHO guidelines recommend artemisinin-based combination therapies (ACTs) as first-line therapy
• Examples include artemether plus lumefantrine, artesunate plus amodiaquine, artesunate plus mefloquine, artesunate plus sulfadoxine-pyrimethamine, dihydroartemisinin plus piperaquine

Severe falciparum malaria:

• A parasite counts of more than 2% will usually need parenteral treatment irrespective of clinical state
• Intravenous artesunate is now recommended by WHO in preference to intravenous quinine
• If parasite count > 10% then exchange transfusion should be considered
• Shock may indicate coexistent bacterial septicaemia - malaria rarely causes haemodynamic collapse

Question 54#

Which one of the following features is not associated with Lyme disease?

A. Jarisch-Herxheimer reaction

Correct Answer D: Lyme disease is associated with erythema chronicum migrans.

Lyme disease: features:
Early features: 

• Erythema chronicum migrans (small papule often at site of the tick bite which develops into a larger annular lesion with central clearing, occurs in 70% of patients)
• Systemic symptoms: malaise, fever, arthralgia

Later features:

• CVS: heart block, myocarditis
• Neurological: cranial nerve palsies, meningitis
• Polyarthritis

Question 55#

A 31-year-old woman is admitted to hospital. As part of a liver screen the following results are obtained:

• Anti-HBs Positive
• Anti-HBc Positive
• HBs antigen Negative

Anti-HBs = Hepatitis B Surface Antibody; Anti-HBc = Hepatitis B Core Antibody; HBs antigen = Hepatitis B Surface Antigen

What is the patient's hepatitis B status?

A. Previous immunisation to hepatitis B

Correct Answer C: 

Hepatitis B serology:

Interpreting hepatitis B serology is a dying art form which still occurs at regular intervals in medical exams. It is important to remember a few key facts: 

• Surface antigen (HBsAg) is the first marker to appear and causes the production of anti-HBs
• HBsAg normally implies acute disease (present for 1-6 months)
• If HBsAg is present for > 6 months then this implies chronic disease (i.e. Infective)
• Anti-HBs implies immunity (either exposure or immunization). It is negative in chronic disease
• Anti-HBc implies previous (or current) infection. IgM anti-HBc appears during acute or recent hepatitis B infection and is present for about 6 months. IgG anti-HBc persists
• HbeAg results from breakdown of core antigen from infected liver cells as is therefore a marker of infectivity

Example results: 

• Previous immunization: anti-HBs positive, all others negative
• Previous hepatitis B (> 6 months ago), not a carrier: anti-HBc positive, HBsAg negative
• Previous hepatitis B, now a carrier: anti-HBc positive, HBsAg positive