Gastrointestinal Infections Flashcards
define primary peritnotis
Spontaneous bacteria peritonitis SBP
infection of the ascitic fluid in the peritoneal cavity without an evident source of infection. Can be from a manifestation of chronic impairment of liver function or just an infection
what are some risk factors for primary peritonitis?
ascites cirrhosis liver disease portal hypertension increased permeability of intestinal mucosal barrier
which organisms usually cause primary peritonitis?
Gram negative bacilli
E. Coli
Klebsiella
Gram Positive cocine
streptoccocus
enterococcus
*ususally monomicrobial and anaerobes are rare
what are the signs and symptoms of primary peritonitis?
Fever* Abdominal pain* nausea/vomiting diarrhea rebound tenderness decreased or absent bowel sounds increased WBC
what three methods are used to diagnose primary peritonitis?
- imaging
- paracentesis:a. inc WBC: PMN> 250/mm3 b. gram stain of organism
- cultures: blood/ascitic acid culture
what agents can be used to treat primary peritonitis?
- 3rd gen cephalosporins: ceftriaxone, cefotaxime
- fluoroquinolones: levofloxacin, norfloxacin
- aminoglycosides + [ampicillin or penicillin] : gentamycin/tobramycin
- [vancomycin or clindamycin] + [ciprofloxacin or aztreonam or aminoglycoside]
what are the advantages of ceftriaxone or cefotaxime for primary peritonitis? disadvantages?
\+broad spectrum \+single agent \+well tolerated -No enterococcus coverage -resistance
what are the side effects of 3rd generation cephalosporins?
diarrhea-5% vomiting-5% rash-rare hypersensitivity reaction-rare pseudomembranous colitis-rare
what are the advantages of levofloxacin norfloxacin for primary peritonitis? disadvantages?
\+broad spectrum \+available po and IV -resistance? -could exacerbate myasthenia gravis -tendon rupture/inflammation increased risk with concurrent corticosteriouds, organ transplant recipients and patients >60 -diarrhea/nausea -dizziness/headahce -Qtprolongation -seizure -no divalent cations -no enterococcus coverage
what are the advantages of amino glycoside plus [ampicillin or penicillin]?
\+broad spectrum \+bacteriocidal combo for enterococcus -AMG requres close drg monitoring -neuro/ototoxic -irrevirsible -nephrotoxic
what are the adverse effects of vancomycin?
N/V
red man syndrome
rash/pruritis
Serious:
ototoxicity, nephrotoxicity, neutropenia, throbocytopenia, anaphylaxis
what are the adverse effects of clindamycin?
Rash GI symptoms Serious: pseudomembranous enterocolitis increased LFTs BBW: clostridium dificille diarrhea
how long should you see improvement with peritonitis antibiotics?what is the duration of therapy?
48 hours
10-14 days
5 days if patient responds well, discharging or insurance issues
when should you consider SBP prophylaxis for patients?
- Cirrhosis with and prior SBP
- ascitic fluid protein concentration <1g/dL
- cirrhosis with gastrointestinal bleed (+/- ascites)
how should you treat each of those patients that need SBP prophylaxis?
- indefinite or until transplantation or resolution of ascites: norfloxacin or TMP/SMX or ciproflox
- give following only during hospitalization: norfloxacin or TMP/SMX or ciproflox
- use primary peritonitis treatment for 7 days
what are the SBP prophylaxis doses of norfloxacin, TMP/SMX and Cipro?
norfloxacin 400mg po q24h
TMP/SMX
Cipro
what defines secondary peritonitis?
contamination of peritoneal cavity by intestinal contents due to: Gi performation malignancy trauma diverticulitis/ appendicitis bowel obstruction/ strangulation mesenteric vascular obstruction pancreatitis surgical contamination complication of peritoneal dyalisis ruptured abscess
what defines an intraabodminal abscess?
collection of necrotic tissue, bacteria, leukocytes that form over a period of days to years. it prevents the spread of infections. Usually complications of primary or secondary peritonitis: appendicitis/diverticulitis trauma biliary tract lesion abodominal surgery perforated perptic ulcer IBD pancreatitis
if you have an intraabdominal infection in the stomach, what are the likely organisms?
streptococcus and lactobacillus
if you have an intraabdominal infection in the upper intestine, what are the likely organisms?
streptococcus
PEK
lactobacillus
if you have an intraabdominal infection in the distal ileum, what are the likely organisms?
streptococcus
EK
bacteroides
clostridium
what are the most likely organisms that will cause an intra abdominal infection?(secondary peritonitis)
Aerobic: PEK Ecoli* most likely
Anerobic: B. Fragilis*, fusobacterium spp, Clostridium spp
what are the signs and symptoms of Secondary peritonitis?
abdominal pain/tenderness/distenion fever or hypothermia decreased or absent bowel sounds tachycardia increased WBC (+left shift) decreased mental status hypotension anorexia/nausea/vomiting
how d other diagnose the IAI?
- ultrasound
- computerized tomography
- needle aspiration of peritoneal cavity
- blood cultures
- exploratory laparotomy
which medications are NOT recommended to cover B.Fragilis?
cefotetan
clindamycin
ceftizoxime
which medications have good coverage of B. Fragilis?
metronidazole ampicillin/sulbactam ticarcillin/clavulanic pip/tazo tigecycline moxi cefoxitin
what constitutes a high risk patient for secondary peritonitis?
advanced age >70 yo degree of peritoneal involvement diffuse peritonitis presence of malignancy low albumin level comorbidity and agree of organ dysfunction delay in initial intervention >24 hours APACHE II score > 15 poor nutritional status
how do you treat patients that have mild to moderate infections (i.e Not high risk)?
Chose one option ALL Intravenous 1. cefoxitin 2g q6h 2. ertapenem 1g q24h 3. moxi 400mg q24h 4. tigecycline 100mg x 1, 50mg q12h 5. ticarcillin/clav 3.1g q6h Combine Metronid 500mg q8h with: 6. cefazolin 1-2g q8h 7. cefuroxime 1.5g q8h 8. ceftriaxone 1g q24h 9. cefotaxime 1g q8h 10. cipro 400mg q12h 11. levo 750mg qw24h
who should be covered for enterococcus spp?
- enterococcus is recovered form culture
- predominant organism on culture is enterococcus and patient not responding to antibiotics
- post op infection, previous abc selecting for enterococcus, immunocompromised, valvular heart dx, prosthetic intravascular material
which medications cover enterococcus?
- piperacillin/tazo
- dori/imi/meropenem
- tigecycline
- ampicillin
- ampicillin/tazobactam
- vancomycin
which medications can you use for high risk secondary peritonitis?
- impenem cilastin 500mg-1g IV q6-8h
- meropenem 500mg-1g IV q6-8h
- doripenem 500mg IV q8h
- piperacillin/tazobactm 3.375g IV q6h
Combine metronidazole 500mg iV q8h - cefepime 1-2g IV q8h
- ceftazidime 1-2g VI q8h
- cipro 400mg IV q12h
- levo 750mg IV q24h
what are the risk factors for MRSA?
- chronic dialysis within 30 days
- IV drug use
- history of MRSA infection
- immunosuppressed
- recent broad spectrum antimicrobial tx with minimal improvement (past 90 days)
which agents should you use for IAI if patient is penicillin allergic?
aztreonam +metronidazole + vancomycin
who should get anti fungal therapy for IAIs?
- recently received immunosuppressive therapy
- postoperative or recurrent gastrointestinal perforation or anastotmotic leakages
- perforation of gastric ulcer on acid suppression or malignancy
- fungi recovered form culture: usually c. albicans
what is the c. albicans treatment?
fluconazole 12mg/kg (800mg) IV/Po x 1, 6mg/kg (400mg) q24h
what if the patient is flucanazole-resistant?
- caspofungin 70mg x 1, 50mg IV q24h
- micafungin 100mg iv q24h
- anindulafungin 200mg x 1, 100mg IV q24h
how long should antibiotic treatment be for secondary peritonitis?
4-7 days
what are the oral treatment options for IAIs?
- moxifloxacin
- cipro/levofloxacin PLUS metronidazole
- oral cephalosporin plus metronidazole
- amox/clavulanate
what is cholecystitis?
inflammation of the gall bladder
what is cholangitis?
inflammation of biliary ductal system
what pathogens are implicated in cholangitis?
aerobic gram N bacillli (enterobacteria)
anaerobes: b. fragilis
enteroccoccus (not always)
what are the signs and symptoms of cholangitis?
N/V abdominal pain/ distension/tenderness fever increased LFTs, TBilirubin, alk phos, amylase, Increased WBC Right upper quadrant pain jaundice
how do you treat mild to moderate community acquired acute cholecystits?
cefazolin
cefuoxime
ceftriaxone
how do you treat sever community acquired acute cholecystits or acute cholangitis ?
use the high risk Community acquired IAI regimen
how do you treat HCAI biliary infections
add vancomycin to above regimen
how do you diagnose C. difficile?
- presence of symptoms like diarrhea
2> a stoo test postivie for C. difficile toxins or toxigenic c. difficille or colonscopic findings demostrating pseudomembranous colitis
what are some risk factors for acquiring CDAD?
- laxatives
- enemas
- GI tract manipulation
- gastric acis suppression: PPIs
- > 64 yo
- antibiotics exposure, clinda, ampicillin, cephalosporins, fluroquinolones
- poor antibody response
- chemotherapy
- severe underlying illnes
what are the signs and symptoms of CDAD?
sever diarrhea fever lower abdominal pain/tenderness N malaise leukocytosis
what complications can occur with CDAD?
dehydration toxic megacolon bower perforation renal failure hypoalbuminemia sepis dead
what constitutes mild to moderate CDAD?
diarrhea and abodminal cramping withougth systemic symptoms
WBC < 1.5 x premorbid level
how do you treat mild to moderate CDAD?
metronidazole 500mg po q8h x 10-14 days
if worsening try vancomycin for severe CDAD
what constitutes severe CDAD?
abundant diarrhea abodminal pain leukocytosis fever or other systemic symptoms WBC >15000 or SCr >1.5 x premorbid
how to treat severe CDAD
vancomycin 125mg po q6h x 10-14 days
if hypotension, shock ileum or megacolon: can add IV metronidazole
how to treat 2nd relapse of CDAD?
vanco taper
125mg q6h x 10-14 days, 125mg q12h x 7 days, 125mg q24 h x 7, 125mg q2-3days for 2-8 wks
what is alternative tx for CDAD?
fidaxomicin 200mg po q12h
nitazoxanide 500mg po q12h (LAST EFFORT)
rifamicin 200-400mg po q8-12h
IVIG 150-400mg/kg IV q24hx x 1-3 doses
what should CDAD patients avoid?
cholestyarmine colestipol cuz adverse effect of constipation and will decrease efficacy of vancomycin due to binding
non pharm prevention of CDAD?
strict hand hygeine appropriate contact precauseions proper environmental contamination antimicorbial stwardship forumulary restrictions prudent use of PPIs
