Infection Flashcards
What is the 1st line antibiotic for perioperative antibiotic prophylaxis?
Allergy?
First-line treatment: intravenous cefazolin
In patients with beta-lactam allergy: clindamycin or vancomycin
Which patients may require IV metronidazole in addition to IV cefalozin for perioperative prophylaxis?
Small intestinal obstruction
Appendectomy
Colorectal surgery
What are the most common causes of a post op fever?
Surgical site infections Pneumonia Catheter related UTI Primary blood stream infections Febrile drug reaction
What types of pnuemonia are surgical patients at risk of?
Ventilator associated
HAP
Aspiration
What bacteria causes necrotising fasciitis?
How does it present?
Group A strep most commonly (strep pyogenes)
Cloudy grey discharge +/- crepitus (gas in subcutaneous tissue)
How does c diff present?
What is the complication?
- Watery diarrhoea (can be blood stained)
- Colicky abdominal cramps
- Fever w/ Rigors
- Raised WCC
Complication: Risk of toxic megacolon (do AXR)
What type of bacteria is C diff? How does it cause disease?
- ANAEROBIC gram +ve rod
- forms toxins that are cytotoxic to mucosal cels
- causes pseudomembranous colitis (PMC)
What antibiotics cause C diff?
- CEPHALOSPORINS MOST COMMON (spores)
also: Clindamycin/ciprofloxin/penicillins
What is the management of c diff?
PO metronidazole for 10-14 days
PO vancomycin if severe / unresponsive
(combine both if life threatening)
What is the diagnostic test for C diff?
Stool sample
-PCR for protein followed by ELISA for toxins
What would you see in C diff on sigmoid/colonoscopy
pseudomembranous yellow plaques
Treatment for toxic megaolon?
May need urgent colectomy
Define pyrexia of unknown origin
Fever >38 for >3 weeks which cannot be diagnosed after a week in hostpiral
List some causes of pyrexia of unknown origin
Neoplasia
- Lymphoma
- Hypernephroma
- Preleukaemia
- Atrial myxoma
Infections
- Abscess
- TB
Connective tissue disorders
Criteria for HAP diagnosis?
HAP
- Pneumonia if been admitted with 5 days
- If sent home and get pnuemonia within 4-6 weeks
What bacteria are more likely to cause HAP
Different profile of organism compared with CAP
- Gram negative enterobacteria
- Staphylococcus aureus
- Pseudomonas
- Klebsiella pneumoniae
Treatment for HAP?
HAP
- IV aminoglycoside e.g. gentamicin (gram neg cover) and IV piperacillin Tazocin
What are the three types of influenza virus? Which cause most cases?
A, B, C
A and B are majority
How are children given the flu vaccine?
Intra-nassally
At 2-3yrs then annually
Live vaccine
How does flu present?
Most asymptomatic Sudden onset high fever Headache Muscle / joint aches Non productive cough Severe malaise
If someone with flu develops a productive cough or raised inflammatory markers?
Bacterial superinfection over influenza
Most commonly s aureus or strep pneumoniae
Management of flu?
Supportive
Antiviral if high risk (neuraminidase inhibitors eg zanamivir / oselatamivir)
Complications of flu?
Primary influenza pneumonia
- Haemorrhagic pneumonia
- Can progress to ARDS
Secondary bacterial pneominia
- Febrile and productive cough after flu symptoms have improved
- Most common pneumoniae
URTI eg AOM, sinusitis, croup
Myositis and rahbdomyolyis
Myocarditis
Encephalitis
How does mumps present?
MUMPS
- Prodrome of fever, malaise, myalgia
- Then parotitis -U/L → B/L
- causes earache and pain on eating
- dry mouth because salivary glands blocked
Clinical diagnosis is often adequate ☺
How is mumps spread?
Resp droplets taken into parotid gland then spreads to other tissues (kissing)
NB notifiable disease
What is the incubation period and when is mumps infective?
Infective 7 days before and 9 days after parotid swelling starts
Incubation period = 14-21 days
What are some complications of mumps?
Orchitis → infertility:50% of POSTpubertal males,
- Usually 4/5 days after start of parotitis
Hearing loss - usually unilateral and transient
Meningitis (15%) -mild and self limiting
Acute pancreatitis
What causes malaria?
Plasmodium protozoa
Spread by female Anopheles mosquito
What are the different types of plasmodium?
1) Plasmodium falciparum (most common cause of malaria)
2) Plasmodium vivax
3) Plasmodium ovale
4) Plasmodium malariae
What are some protective factors for malaria?
Sickle cell trait
G6PD deficiency
How does malaria present?
- Flu like symptoms
- Headache
- Excessive sweating (diaphoresis)
- High fever
- Haemolytic anaemia - weakness, paleness, dizziness
- D&V
- Confusion/seizures if sever
Note can present up to a year post travel
Sx may occur from 6 d of infection → many months later Phase 1 (≤ 1hr) Shivering Phase 2 (2-6hr) Fever (HIGH temp > 41), flushed, dry skin, nausea + vomiting, headache Phase 3 (3hr) – Cold Sweats as temp falls
When do you get spikes in fever with Malaria?
Falciparum + Vivax + ovale = EVERY OTHER DAY (tertian)
Malariae = Every 3rd day (quatrtan)
What signs do you get with malaria?
Spleno/hepatomegaly ± abdominal tenderness
Jaundice
Myalgia
What is the diagnostic investigation for malaria?
d
What is the diagnostic investigation for malaria?
THICK AND THIN BLOOD SMEAR
What other bloods would you do in malaria and what would you see?
FBC:
- anemia
- thrombocytopenia (may cause bleeding)
Creatinine
(AKI picture)
Clotting
(can get DIC)
ABG/lactate
-acidosis
Urinalysis
-heamaglobinuria (nephritic)
Glucose
-hypoglyceamia
How does severe malaira (usually falciparum) cause severe organ dysfunction?
Infected erythrocytes deform and stick to endothelial vessels
This prevents them from being removed by the spleen
These occlude capillaries causing microinfarcts
What organ damage can occur in severe malaria?
Kidneys
- Flank Pain
- Oliguria
- Hemoglobinuria
Cerebral
- Hallucinations
- Confusion
- LOC / coma
HF
Pulmonary oedema
Shock
What is the treatment for uncomplicated falciparum malaria?
UNCOMPLICATED falciparum malaria
- Artemisinin combination therapy (ACT)
e. g. artemether with lumefantrine
If not available:
- Quinine
- AtovaQUONE with proguanil
What are features of severe malaria?
SEVERE MALARIA FEATURES
- ↓GCS/siezures
- AKI/ haemaglobinuria (from acute tubular necrosis)
- Shock
- Hypoglycaemia
- Pulmonary odema/ARDS
- Anemia
- DIC/spont bleeding
- Acidosis (pH <7.3)
What is the treatment for severe malaria?
Treatment for severe malaria
-IV Artesunate
What is the treatment of choice for non falciparum malaria?
Non falciparum malaria=Chloroquine (can cause blindness)
this is because falciparum is resistant to chloroquinine
Fever following fresh water exposure?
Schistosomiasis (snails
Leptopirosis (rats-weil disease)
Fever following contaminated food and water / raw meat / fish
Enteric fever Shigella Salmonella Campylobacter Amoebiasis Helminth infection Hep A and E
What does eosinophilia in a returning traveller indicate?
Parasitic infection
Describe symtpoms of Campylobacter infection?
Complication?
Campylobacter
- A flu-like prodrome
- Followed by crampy abdominal pains, fever + diarrhoea (may be bloody)
- Complications include Guillain-Barre syndrome
Which antibiotics have a beta lactam ring?
Penicillins Cephalosporins Monobactam Carbapenems Carbacephems
