Infections and antibiotics (2) Flashcards
A 35 year old man presents to his GP with a persistent dry cough and general malaise for the last 3 weeks. Initially he thought he just had a cold with coryzal symptoms and a headache, but he is not improving. He has also noticed a rash. On examination he has a few crackles and wheeze at the right base. His GP sends him for a CXR (picture)
What does an x ray show?
CXR confirms patchy shadowing at R base
Describe the rash
Target lesions – erythema multiforme
A 35 year old man presents to his GP with a persistent dry cough and general malaise for the last 3 weeks. Initially he thought he just had a cold with coryzal symptoms and a headache, but he is not improving. He has also noticed a rash. On examination he has a few crackles and wheeze at the right base. His GP sends him for a CXR (picture)
What do you think is a diagnosis and give reasons
Atypical pneumonia – Mycoplasma pneumonia due to:
- insidious onset
- dry cough
- extra-pulmonary features such as the rash
List 2 investigations which may help to establish a diagnosis of mycoplasma pneumonia
- serology for mycoplasma
- cold agglutin test
- haemolytic anaemia
- raised ESR
Treatment for mycoplasma pneumonia
- Amoxicillin 500mg – 1 g tds + Erythromycin 500mg qds 14 days
- Doxycycline is also effective against mycoplasma
Possible complications of mycoplasma pneumonia
- Rashes → erthema multiforme, erthema nodosum, urticaria
- Haemolytic anaemia
- Cold agglutinin disease
- Aseptic meningitis
- transerve myelitits
- Guillaine- Barre
- Myocarditis
- Pericarditis
What’s Cold Agglutinin Disease?
Cold agglutinin disease (CAD)
- a rare autoimmune disease characterized by the presence of high concentrations of circulating cold sensitive antibodies
- It is a form of autoimmune hemolytic anemia
Pathology:When affected people’s lood is exposed to cold temperatures certain proteins that normally attack bacteria (IgM antibodies) attach themselves to red blood cells and bind them together into clumps (agglutination). This eventually causes red blood cells to be prematurely destroyed (hemolysis) leading to anemia and other associated signs and symptoms
Cause:Cold agglutinin disease can be primary (unknown cause) or secondary, due to an underlying condition such as an infection, another autoimmune disease, or certain cancers
Treatment: depends on many factors including the severity of the condition, the signs and symptoms present in each person, and the underlying cause
Treatment of cold agglutinin disease
- Avoid cold weather.
- Treat the underlying lymphoma.
- No cold drinks; all drinks should be at room temperature (or above).
- Requires heater to maintain temperature in cold places.
Treatment with rituximab has been described
A homeless man is sent to hospital from a hostel feeling unwell – he complains of dyspnoea and a cough productive of purulent sputum and said this started 5 days ago after he collapsed drunk in a doorway. On examination he is febrile temp 39 C, pulse 120 bpm and Sats 90% on air.
What does the X-ray show?
R upper lobe pneumonia
A homeless man is sent to hospital from a hostel feeling unwell – he complains of dyspnoea and a cough productive of purulent sputum and said this started 5 days ago after he collapsed drunk in a doorway. On examination he is febrile temp 39 C, pulse 120 bpm and Sats 90% on air.
What is the likely diagnosis and why and what organisms are involved?
Aspiration pneumonia as:
- usually affects R side and if aspiration occurs while prone will be in upper lobe
- common organisms – anaerobic organisms but also aerobic organisms
A homeless man is sent to hospital from a hostel feeling unwell – he complains of dyspnoea and a cough productive of purulent sputum and said this started 5 days ago after he collapsed drunk in a doorway. On examination he is febrile temp 39 C, pulse 120 bpm and Sats 90% on air.
Management
- ABC - Oxygen, IV access, BP
- ABGs, blood cultures, sputum culture
- Treat with oxygen, amoxicillin 1g tds + metronidazole 400mg tds for 7-10 days.
A 28 year old cachexic man is admitted to hospital with a high fever and productive cough – o/e he has crackles and bronchial breathing with reduced AE at the left base.
This is part of your examination, what do the pictures suggest?
- Infected injection site/track marks
- Lung abscess at L base
*likely due to Staph aureus infection
A 28 year old cachexic man is admitted to hospital with a high fever and productive cough – o/e he has crackles and bronchial breathing with reduced AE at the left base.
List 2 other complications that may occur in this man (directly related to above pathogen).
- Injection site abscesses
- R side endocarditis
A 28 year old cachexic man is admitted to hospital with a high fever and productive cough – o/e he has crackles and bronchial breathing with reduced AE at the left base.
Management
Diagnosis: lung abscess due to Staph Aureus infection
Management:
- ABC
- ABG
- Sputum
- blood culture
Amoxicillin 500mg 1g tds + flucloxacillin 500mgs qds for min 14 days
IV drug user with a lung abscess due to Staph aureus infection.
What further Ix do we need to consider?
- Hep B and Hep C
- HIV
- TB
- Consider managing issue of addiction – methadone, rehab programme
- forensic hx
- sexual hx and STIs screen
A 23-year-old lady attends surgery complaining of a 2-day history of increased urinary frequency and dysuria. Urinalysis is positive for nitrates, leucocytes and protein. She describes no previous similar episodes.
Are there any other clinical features you would want to consider?
Differentiate between lower vs upper UTI and an uncomplicated vs complicated UTI
(another flashcard)
Uncomplicated vs complicated UTI
Uncomplicated UTI → infection of urinary tract by a usual pathogen in a person with a normal urinary tract and with normal kidney function
Complicated UTI → UTI when one of more factors are present that predispose the person to persistent infection, recurrent infection or treatment failure:
- abnormal urinary trace eg calculus, vesicoureteric reflux, reflux nephropathy, neurogenic bladder, indwelling catheter, urinary obstruction, recent instrumentation
- Virulent organism eg staph aureus
- Impaired host defences eg poorly controlled DM, immunosuppressive Rx
- Impaired renal function
Management of a lady with uncomplicated UTI
- Do not routinely send urine for culture in women with uncomplicated UTI
- Symptomatic relief →analgesia if required. No evidence for cranberry juice in UTI treatment
- Antibiotic to all women with suspected UTI
3-day antibiotic course for most women – either nitrofurantoin 100mg MR bd 3/7 or trimethoprim 200mg po bd 3/7 (follow local guidelines)
- For women with mild symptoms who have normal immunity, normal renal function and a normal renal tract, treatment can be delayed if patient wishes to see if symptoms resolve without treatment – esp if dipstick is negative for nitrites and leucocyte (indicating a low probability of a UTI)
- Safety netting – seek medical attention if fever, loin pain or if not responding to first choice antibiotic
A 3 day history of vulval itch and white non-offensive vaginal discharge.
Can you list 2 treatment options?
- Clotrimazole pessary 500mg stat
- Clotrimazole cream PV
- Clotrimazole cream topically externally
- Oral fluconazole (contraindicated in pregnancy)
Diagnostic algorithm for UTI in adults
27 year old lady presents with a localised tender and erythematous area in her left breast. She has a 2 month old daughter and is breastfeeding. She is otherwise well in herself.
What is the most likely organism causing this condition?
Staph Aureus
A 27 year old lady presents with a localised tender and erythematous area in her left breast. She has a 2 month old daughter and is breastfeeding. She is otherwise well in herself.
How would you manage this?
- Relieve pain and discomfort Paracetamol / ibuprofen. Warm compress / bath or shower in warm water – pain relief and to aid milk flow
- Continue to breast feed if possible – including from the affected breast. If too painful the advise woman to express
- Identify and manage any predisposing factors for mastitis eg poor infant attachment to breast, reduced number or duration of feeds.
- Advise rest, keep well hydrated and avoid tight clothing. If nipple soreness or damage then manage this also
- Prescribe an oral antibiotic if nipple fissure is infected, symptoms have not improved (or are worsening) after 12-24 hours despite effective milk removal.
- If breast milk culture available then treat with appropriate antibiotic (BUT this is NOT common practice in primary care - only done if recurrent severe infection / suspicion re hospital acquired infection or severe deep burning breast pain suggestive of ductal infection).
- Otherwise treat empirically with Flucloxacillin 500mg po qds for 10-14 days. If penicillin allergic use either erythromycin 250-500mg qds or clarithromycin 500mg po bd for 10-14 days.
Can a patient with mastitis continue to breastfeed?
Continuing breast feeding should be encouraged as this helps to drain the affected segment of the breast
It is important to empty the affected breast and if it is too tender for feeding to continue, the baby should be fed from the non-infected breast and milk expressed from the infected one.
MoA of macrolides
Inhibition of bacterial protein biosynthesis, thought to happen by preventing peptidyltransferase from adding the peptidyl attached to tRNA to the next amino acid as well as inhibiting ribosomal translocation
