BACTERIAL INFECTIONS IN CORE SYSTEMS Flashcards
LOWER UTI, CAUSES RISK FACTORS AND SYMPTOMS
CAUSES: Commonly bacteria
- Usually E. coli in bladder/ urethra from GIT.
RISK FACTORS:
(1) Females - urinary system + GIT in close proximity
(2) Sexual activity
(3) Pregnancy
(4) Genetic predisposition
(5) Post-menopausal
(6) Diabetes
SYMPTOMS:
(1) Increased urination frequency - polyuria
(2) Burning in urination - dysuria
(3) Cloudy urine
(4) Strong-smelling urine
(5) Lower abdominal discomfort
UTI: 1ST LINE TREATMENT FOR WOMEN THAT AREN’T PREGNANT AND 2ND LINE TREATMENT
- Nitrofurantoin
- 100 mg M/R
- BD
- 3 day course (increase duration if pregnant)
2ND
Fosfomycin/ pivmecillinam
CAUSES, SYMPTOMS OF PNEUMONIA
Strep.pneumoniae pneumococal, typically ‘at risk’ groups.
fever, loss of appetite, unwell, shivering, chest pain, others
TREATMENT FOR PENUMONIA and PREVENTION
Depends on severity, organism and type, e.g. CA vs HA oral antibiotics, e.g. amoxicillin, IV antibiotics (hospital/severe).
Vaccine, PPV against pneumococcal
PATHOPHYSIOLOGY and SYMPTOMS OF H PYLORI
Causes damage to the stomach and duodenal epithelial lining via multiple mechanisms. Can cause gastritis (inflammation). Can lead to damage and later ulcers. Inflammation and other effects of H.pylori can also lead to gastric cancer in chronic infection.
Abdominal pain (burning), nausea, bloating, belching.
TREATMENT FOR H PYLORI
PPI + 2 antibiotics: amoxicillin (1000mg/BD) + either clarithromycin (500mg BD) or metronidazole (400mg BD) for 7 days
INFECTIVE ENDOCARDITIS: CAUSES AND SYMPTOMS
Usually bacterial and in pt. with heart valve replacement or damage (rare) caused by commonly s.aureus or strep.
Symptoms: fever, chills, heart murmurs, tiredness/fatigue, cough, headache, shortness of breath, night sweats & others
TREATMENT FOR INFECTIVE ENDOCARDITIS
Depends on no. factoirs, e.g. a penicillin (+gentamicin, s.pyogenes) flucloxacillin (s.aureus). if serious, empiric treatmewnt e.g. ampicillin or (vancomycin, MRSA) duration 2-6 weeks. surgery.
IMPETIGO CAUSES AND DIAGNOSIS
Break in skin, infection with s.aureus or s.pyogenes.
Lesions start, e.g. pustules that release exudate forming a crust (non bullous) or blisters that burst forming crust (bullous)
symptoms: swollen glands, fever, diarrhoea (esp. bullous)
WHAT IS THE MOST COMMON CAUSE OF INFECTION IN THE GIT and treatment for most GIT infections
Faecal oral transmission, No treatment - normally self-limiting
Stay hydrated
What are the causes and symptoms for BV?
Overgrowth of anaerobic bacteria in the vagina, symptoms: Discharge:
- White/ pale grey discharge
- Milky discharge
- Fishy-smelling
What is the treatment for BV?
Oral metronidazole 400mg BD, 5-7 day treatment, alternatively
2g single dose of metronidazole gel
similarities and differences in symptoms between BV and Thrush
S: increased vaginal discharge, white discharge
D: BV discharge can be grey, discharge in BV is smooth, thrush is curdled, thrush has no odor, thrush itches and burns
Which skin layer does acne, impetigo & cellulitis affect
acne - epidermis hair follicle
impetigo - epidermis
cellulitis - dermis, subcutaneous fat
treatment for impetigo? localised vs systemic
good hygiene
LOCALISED
- Topical fusidic acid for 5 days
- Topical mupirocin 2% for 5 days if MRSA
SYSTEMIC:
- Oral flucloxacillin 250-500mg QDS for 7 days
- Clarithromycin 250-500mg BD for 7 days (if allergic)
Cellulitis? causes and symptoms?
inflammation of the skin and subcutaneous tissues caused by s.pyogenes most common, or s.aureus in damaged skin
symptoms:(1) Red
(2) Hot
(3) Swelling/ inflammation
(4) Painful
treatment for mild cellulitis vs gram negative cellulitis
mild: flucloxacillin (clarithomycin if penicillin allergy), 500mg QDS for 7 days
gram -ve, broad spectrum antibiotic e.g. amoxicillin
Bacterial conjunctivitis: causes and its symptoms
(1) S. aureus
(2) H. influenzae
(3) S. pneumoniae
symptoms: (1) Thick + yellow discharge (mucopurulent)
(2) Gritty feeling in eye
(3) Pink/ red eye
First line treatment for bacterial conjunctivitis and second line treatment
1st: (1) Self-care
(2) Bathe + Clean
2nd: A
(1) OTC Topical Antibiotics
- Chloramphenicol 0.5% drops
- Chloramphenicol 1% ointment
(2) Self-care
Otitis externa, causes and symptoms?
infection of the outer ear,
causes: mainly bacterial
s.aureus, p.aeruginosa - can also be fungal
symptoms:
pain, itchiness, discharge, temporary/slight hearing loss, feeling of pressure
treatment for otitis externa?
(1) Self-care
- Pain relief
- Localised heat
(2) Clotrimazole if fungal
(3) If bacterial:
- Topical acetic acid 2%
- Topical antibiotic - neomycin
- Corticosteroid - betamethasone
Otitis media? causes and symptoms
Infection of the middle region of the ear, most common cause of ear pain in children
causes:
(1) Usually viral
(2) Can be bacterial:
- S. pneumoniae
- H. influenzae
symptoms:
(1) Ear ache
(2) Fever
(3) Vomiting
(4) Fatigue
(5) Slight hearing loss
Treatment for otitis media?
(1) Self-care
- Pain relief
(2) If severe
- Antibiotics (amoxicillin)
What are the similarities and differences between the symptoms of otitis externa and otitis media?
(1) Similiarities:
- Pain/ ear ache
- Slight hearing loss
(2) Differences:
- externa is itchy, with discharge + feeling of pressure
- media gives fatigue, fever + vomiting
What is the causes and symptoms of a sore throat?
Usually viral, can be bacterial. Strep throat is caused by airborne droplets.
(1) Pharyngitis - throat inflammation
(2) Tonsillitis - tonsil inflammation
What is the treatment for a sore throat?
at home
-salt gargle
-increased fluids
-painkillers
Phenoxymethylpenicillin - severe bacterial infections
- Covers group A streptococcus (GAS)
What is septic arthritis and it’s treatment?
Infection of the joints, flucloxacillin for 4-6weeks
What is osteomyelitis and its treatment?
Infection of the bone marrow
1st-flucloxacillin for 6 weeks
sometimes with the addition of fusidic acid/rifampicin for first 2 weeks
What is the role of the pancreas?
Blood glucose regulation
What is bacterial meningitis?
Infection of the CNS
What is the cause of bacterial meningitis?How does this differ for old/young patients?
Older children/adults: s.pneumoniae, N. meningitidis
young children
h.influenzae
What are the symptoms of bacterial meningitis?
headache, stiff neck, fever, non-blanching rash-N. meningitidis, photophobia, altered consciousness
What is the treatment for bacterial meningitis?
If meningococcal (N. meningitidis): iv benzylpenicillin
in hosp: IV ceftriaxone/cefotaxime
can also use corticosteroid - dexamethasone
What are the preventative measures for bacterial meningitis?
vaccination
what does the bacterial meningitis vaccination include?
(1) HiB
(2) MenB
(3) MenC
(4) MenACWY
What is sepsis and how does it affect the body?
An inflammatory immune response to infection, endo and exotoxins damage tissues and organs
How do the 3 types of endo/exotoxins damage the body’s tissues and organs?
type1-disrupt host cell
type2-destroy host cell membranes to invade and interrupt host defence
type3-disrupt host cell defence to allow spreading of infection
what are the underlying infections that can cause sepsis? and the most common infection sites leading to sepsis?
usually bacterial:gram+ (s.aureus)
gram-(e.coli)
less commonly fungal/viral
(1) Lungs (50%)
(2) Urinary tract (20-25%)
(3) Abdominal (15-20%)
(4) Skin/ soft tissue (10-15%)
what are the symptoms of sepsis?
(1) Fever/ low body temperature
(2) Elevated HR
(3) Elevated RR
(4) Low BP
(5) Confusion
(6) Pale blotchy skin & non-blanching rash
(7) Significantly reduced urination
what is the treatment for sepsis?
(1) Antibiotics PRN
(2) IV fluids PRN
(3) Oxygen PRN
What is a nosocomial infection/HCAI?
Healthcare associated infection
What is Clostridium difficile? what is CDI
Gram positive, anaerobic, spore-forming rod
Clostridium (clostridioides) difficile infection
What is the effect of broad-spectrum antibiotics on CDIs?
Increases the infection
Proportional to the duration of exposure to the antibiotic
Which two conditions is a CDI significantly implicated in?
A
(1) AAD - Antibiotic-associated diarrhoea
(2) AAC - Antibiotic-associated colitis
What are the common symptoms of a CDI?
What are the rare symptoms of a CDI?
(1) Mild-moderate diarrhoea
(2) Mild-severe abdominal cramping/ pain
(3) Yellow-white plaques on the intestinal mucosa (only if SEVERE)
RARE:
(1) Fulminant life-threatening colitis (severe + sudden)
(2) Low-severe fever
(3) Dehydration
(1) What are the different categories for CDI severity?
(2) How is the severity determined?
(1) MILD:
ø Normal WCC
ø <3 loose stools in a day
ø 5-7 on Bristol Stool Chart
(2) MODERATE:
ø Increased WCC - >15x10^9/ L
ø 3-5 loose stools in a day
(3) SEVERE:
ø Increased WCC - >15x10^9/ L
ø Acutely increased serum creatinine (+>50%)
ø Temperature >38.5ºC
ø Evidence of severe colitis
ø Stools are no longer relevant in determining severity
(4) LIFE-THREATENING:
ø Hypotension
ø Partial-complete ileus (obstruction of the ileum)
ø Toxic megacolon (rapid widening of the colon)
ø CT evidence of severe disease
What are common risk factors for CDIs?
(1) Increased age
(2) Proximity to infected patients - e.g. hospital staff
(3) Nasogastric tube
(4) Gastric surgery
(5) PPIs
(6) Increased hospital stay
(7) Underlying disease - e.g. IBS
(8) Chemotherapy
(9) Increased exposure to antibiotics
(10) Courses of multiple antibiotics
What antibiotic can cause a CDI?
Any antibiotic
Traditionally: clindamycin
Why can antibiotic therapy increase risk of CDI?
Can affect the healthy flora of the colon
What is the pathogenicity of C. diff? and it’s progression
(1) Antibiotic therapy affecting healthy colon flora
(2) Toxicogenic stains producing A + B toxins
ø Some strains also produce binary toxin (CDT)
(1) Uncolonised
(2) Asymptomatic colonisation
(3) Toxin production
(4) CDI
What does toxin A do in C. diff infections?
(1) Causes fluid secretion
(2) Causes intestinal inflammation
(3) Activates cytokine release
How does the severity of CDI change when binary toxins (CDT) is present?
Increased severity
How is a CDI diagnosed based on clinical symptoms and risk factors?
(1) Diarrhoea
(2) ABx exposure
(3) History - can lead to recurrent CDI
How is a CDI differentially diagnosed?
(1) Cytotoxic assay
(2) Toxigenic culture
(3) ELISA for toxins A + B
(4) PCR for toxin genes
- Presence of the gene does NOT mean presence of the toxin
How is a suspected CDI managed?
(1) Cessation of offending antibiotic
(2) Symptomatic treatment
ø Fluid + electrolyte replacement
ø NOT antidiarrhoeals
(3) Specific ABx therapy usually indicated
What is the first line therapy for treatment of a mild-moderate CDI?
A
(1)
ø Metronidazole
ø 400 mg
ø TDS
ø Oral
ø 10-14 day duration
(2) Switch to 500mg TDS IV if oral FAILS
(3) Switch to VANCOMYCIN if treatment FAILS
What is the first line therapy for treatment of a severe CDI?
(1)
ø Vancomycin
ø 125-500 mg
ø QDS
ø 10-14 days
(2) ORAL vancomycin is ineffective as it is poorly absorbed
Which antibiotic is potentially superior to vancomycin for preventing recurrent CDI?
Fidaxomicin
What is the rarity of recurrent CDI?
Up to 1/3 cases
How does treatment differ for recurrent CDI?
(1) Same treatment as before
(2) Often switched to oral vancomycin or fidaxomicin
What treatment is gaining importance as a possible treatment for recurrent CDI?
Faecal transplantation
What treatment can be administered in recurrent CDI, in addition to antibiotic therapy? Give an example.
Bezlotoxumab
It is a monoclonal antibody
Selective against toxin B
How are CDI controlled in hospitals?
(1) Good infection control - thorough hand washing
(2) Cohorting/ isolation of infected patients
(3) PPE
(4) Increased monitoring
(5) Improved education on ABx use
