Infectious Diseases Flashcards
What are the live attenuated vaccines?
- BCG
- MMR
- Oral polio
- Yellow fever
- Oral typhoid
Describe the clinical presentation of dengue fever
Retro-orbital headache, fever, facial flushing, rash, thrombocytopenia in returning traveller
What is the most likely organism causing diarrhoea in a patient with HIV?
Cryptosporidium parvum
Describe the presentation of Campylobacter infection
- Prodrome, abdominal pain and bloody diarrhoea
- Incubation period 1-6 days
Name the first line antibiotic to treat MRSA
Vancomycin
What is the treatment fo TB?
- Rifampicin, isoniazid, pyrazinamide and ethambutol for two months
- Continuation phase with rifampicin and isoniazid for an additional four months
Name the second line antibiotic to treat MRSA
Linezolid
What is the most common organism causing LRTI in CF patients?
Pseudomonas aeruginosa
How does Giardia cause lactose intolerance?
Decreases the expression of brush-border enzymes in the small intestines
Describe the clinical presentation of typhoid
- Initially systemic upset
- Relative bradycardia
- Abdominal pain, distension
constipation: although Salmonella is a recognised cause of diarrhoea, constipation is more common in typhoid - Rose spots: present on the trunk in 40% of patients, and are more common in paratyphoid
What is the causative organism for typhoid?
Salmonella typhi
Patients with cellulitis who are penicillin allergic can be given what?
Clarithromycin, erythromycin (in pregnancy) or doxycyline
A 35-year-old man who is known to have advanced HIV disease presents with dysphagia and odynophagia. What is the most likely cause of his problems?
Oesophageal candidiasis
A 15-week pregnant woman contacts her GP for advice because her 6-year-old son has recently been diagnosed with erythema infectiosum. She is clinically well and is immune to rubella. The GP arranges serology for parvovirus B19, which reveals parvovirus IgM positive and IgG negative.
What would be the most appropriate management?
Refer to fetal medicine for further tests
Bloods show a recent infection with parvovirus
Describe the transmmission of hepatitis E
Hepatitis E is spread by the faecal-oral route and is most commonly spread by undercooked pork
For a patient undergoing an elective splenectomy, when is the optimal time to give the pneumococcal vaccine?
Two weeks before surgery
Describe the management of genital warts
- Multiple, non-keratinised warts: topical podophyllum
- Solitary, keratinised warts: cryotherapy
Describe the presentation of disseminated gonococcal infection
Tenosynovitis, migratory polyarthritis, dermatitis
Name a risk factor for nvasive aspergillosis
Leading cause of death in immunocompromised patients
What are some of the causes of a false negative Mantoux test
- Immunosuppression - miliaryTB, AIDS, long-term steroid use
- Lymphoma
- Sarcoidosis
- Extremes of age
- Fever
- Hypoalbuminaemia
- Anaemia
A 23-year-old woman presents with a two month history of cough and intermittent fever.
What is the most likely diagnosis?
TB
What is the antibiotic of choice for cellulitis in pregnancy if the patient is penicillin allergic?
Erythromycin
What is the first line treatment in amoebiasis?
Metronidazole
Patient has had 5 doses of tetanus vaccine, with the last dose < 10 years ago.
Which of the following actions should be taken with regards to tetanus?
Don’t require a booster vaccine nor immunoglobulins, regardless of how severe the wound is
Following an occupational exposure (sharps or mucosal splash) from an index case known to be HIV positive with an unknown or detectable HIV viral load, what duration of PEP is recommended?
Give 4 weeks of antiretroviral therapy and arrange HIV testing at 12 weeks
First line treatment for syphilis
Benzathine benzylpenicillin
True or false: a history of rash with penicillin is not a contraindication to using benzylpenicillin or ceftriaxone in meningococcal sepsis?
True
What blood results are associated with trimethoprim?
Can cause tubular dysfunction, leading to hyperkalaemia and increased serum creatinine
Severe hepatitis in a pregnant woman.
What is the most likely diagnosis?
Hepatitis E
What are the most common causes of viral meningitis in adults?
Enteroviruses
What is the management of pneumocystis jiroveci penumonia?
Co-trimoxazole, which is a mix of trimethoprim and sulfamethoxazole
What are the standard tests for HIV screening?
Combination tests (HIV p24 antigen and HIV antibody)
What are the contraindications for IV dex in meningitis?
- Meningococcal septicaemia (a non-blanching purpuric rash)
- Septic shock
- Recently out of surgery
- Immunocompromised
What are the features of secondary syphilis?
- Occurs 6-10 weeks after primary infection
- Systemic symptoms: fevers, lymphadenopathy
- Rash on trunk, palms and soles
- Buccal ‘snail track’ ulcers (30%)
- Condylomata lata (painless, warty lesions on the genitalia )
What are the features of tertiary syphilis?
- Gummas (granulomatous lesions of the skin and bones)
- Ascending aortic aneurysms
- General paralysis of the insane
tabes dorsalis - Argyll-Robertson pupil
What serology is associated with successful treatment of syphilis?
TPHA remains positive, VDRL becomes negative
Pneumonia caused by what organism is associated with cold sores?
Streptococcus pneumoniae
Describe the presentation of parvovirus B19 (fifth disease)
- Fever
- Slapped cheek rash
- In patients with a background of haemolytic anaemia, particularly sickle cell disease - aplastic anaemia
Describe the presentation of CNS lymphoma
HIV, neuro symptoms, single brain lesions with homogenous enhancement
What organism causes BV?
Gardnerella vaginalis
How do you diagnose cellulitis?
Can be diagnosed clinically in primary care - offer oral antibiotics (fluclox first line)
Whais oral hairy leukoplakia?
EBV infections in HIV patients can cause oral hairy leukoplakia, which presents with white patches on the tongue, usually on the lateral borders
True or false: AFB smear is specific for TB
False - all mycobacteria will stain positive (e.g Mycobacterium leprae - leprosy)
What is the management for cellulitis near the nose or eyes?
Co-amoxiclav
Describe the presentation of yellow fever
Yellow fever typically presents with flu like illness → brief remission→ followed by jaundice and haematemesis
When should testing for HIV in asymptomatic patients should be done after possible exposure?
4 weeks
What is the management of suspected bacterial meningitis in patients < 50 years?
IV cefotaxime (or ceftriaxone)
What is the management of suspected bacterial meningitis in patients > 50 years?
Cefotaxime (or ceftriaxone) + amoxicillin
A 29-year-old woman develops severe vomiting four hours after having lunch at a local restaurant. What is the most likely causative organism?
Staph. aureus
A history of Intravenous drug use coupled with a descending paralysis, diplopia and bulbar palsy is characteristic of infection with what organism?
Clostridium botulinum
What strains of HPV cause genital warts?
HPV 6 & 11
How many doses of tetanus vaccine generally confers life-long protection?
5 doses
Which virus is thought to be the cause of Kaposi’s sarcoma?
HHV-8 (human herpes virus 8)