Mirizzi Syndrome

Thanks to Richard for presenting the case of a middle-aged man who presented with acute onset of lower back pain, intermittent abdominal pain, and emesis, found to be septic, work up revealing Mirizzi syndrome causing acute cholangitis which led to klebsiella bacteremia and L spine osteomyelitis! Whoosh!

Clinical Pearls

  • Klebsiella is found along the GI tract and can cause UTIs, pneumonias, osteomyelitis, GI infections, and surgical site wound infections.
  • Charcot triad of pain, fever, and RUQ pain is found in only ~50% of patients who present with acute cholangitis.  So do not rule out the diagnosis if someone doesn’t have all three.
  • Mirizzi syndrome is rare and can be accompanied by acute chonagitis, acute cholecystitis, or acute pancreatitis.  Management involves antibiotics to treat a concurrent infection in the biliary tree as well as surgical resection of the gallbladder and impacted stone.

Differential for hyperbilirubinemia:

Hyperbilirubinemia breakdown

Remember that the most common reasons for conjugated hyperbilirubinemia are extrahepatic causes and include the following:

  • Stones (30-70%)
  • Malignancy (10-50%)
  • Benign biliary strictures (5-30%)
  • Biliary stent obstruction (~20%)


Most common bacteria:

  • E coli (25-50%)
  • Klebsiella (15-20%)
  • Enterococcus (10-20%)
  • Enterobacter (5-10%)

Clinical manifestations

  • Charcot’s triad (~50% have all 3)
    • Fever
    • Abdominal pain
    • Jaundice
  • Reynold’s pentad: (rare, ~5%)
    • Above PLUS
    • Hypotension
    • AMS
  • Cholestatic LFT pattern ⇒ can progress to hepatocellular LFT pattern

Assessment of disease severity

  • Severe (suppurative) cholangitis — Acute cholangitis is considered severe if it is associated with the onset of dysfunction in at least any one of the following organs/systems:
    • Cardiovascular dysfunction – Hypotension requiring pressors
    • AMS
    • Respiratory dysfunction – PaO2/FiO2 ratio <300
    • Renal dysfunction – Oliguria, serum creatinine >2.0 mg/dl
    • Hepatic dysfunction – Prothrombin time-international normalized ratio >1.5
    • Hematological dysfunction – Platelet count <100,000/mm
  • Moderate acute cholangitis — Acute cholangitis is defined as moderate if it is associated with any two of the following:
    • Abnormal WBC count (>12,000/mm3, <4,000/mm3)
    • Fever 39°C (102.2°F)
    • Age (≥75 years)
    • Hyperbilirubinemia (total bilirubin ≥5 mg/dl)
    • Hypoalbuminemia
  • Mild acute cholangitis — Mild acute cholangitis does not meet the criteria for moderate or severe cholangitis at initial diagnosis.


  • For moderate to severe cases, consider admission to the ICU and urgent ERCP/GB decompression.
  • For mild cases, admit to the floor and monitor closely
  • Antibiotics
    • To cover gram negatives, narrow based on sensitivities
    • Duration is typically 7-10 days.
  • Address predisposing cause
    • Elective cholecystectomy after infection has resolved in those with gallstones

Mirizzi syndrome

Obstruction of the common bile duct from extrinsic compression, often from swelling or infection in the cystic duct, which can share a sheath with the CBD.

  • Commonly diagnosed intraoperatively in patients undergoing GB surgery
  • Presentations
    • Pain (54-100%)
    • Jaundice (24-100%)
    • Cholangitis (6-35%)
    • Acute cholecystitis (1/3 of patients)
    • Acute pancreatitis (rare)
  • Labs
    • Elevated bili and ALP
    • Leukocytosis if concurrent cholecystitis, cholangitis, or pancreatitis
  • Diagnosis
    • Imaging
      • Dilatation of the biliary system above the gallbladder neck
      • Presence of impacted stone in GB neck
      • Normal diameter below level of stone
    • US (23-46% sensitive)
    • CT abdomen (can r/o malignancy but sensitivity is 42%, specificity 99%)
    • MRCP (highest sensitivity)
  • Management
    • Surgery
    • Sometimes ERCP can be diagnostic and therapeutic as a temporizing measure to surgery or if patient is too high risk and unsuitable for surgery
    • Antibiotics for treatment of concurrent cholangitis or cholecystitis


Source: https://www.slideshare.net/mohamedfazly31/mirizzi-syndrome-70749345

Neutropenia and Acute Diarrhea… It’s not C.diff, it’s Norovirus (11/28/18)

Elise presented a case of a middle age man with recently diagnosed pancreatic adenocarcinoma on chemo presenting with acute loose watery stools (“too many to count”) and abdominal discomfort. He appeared septic on presentation and was found to be neutropenic. Unfortunately (or fortunately) it is not the typical C.diff colitis, but actually norovirus!

Acute Diarrhea

Definition: defined as watery stool 3x in 24 hours, < 14 days duration

Most are infectious in etiology in an acute setting

Other causes: Ingested osmoles, malabsorption


  • Secretory: High volume, watery, no systemic symptoms, usually due to small intestinal involvement
    • Most common causes are viral (rota and noro), enterotoxin, ETEC, or vibrio chlolarae.
    • Negative fecal WBC
  • Invasive: Smaller volume, bloody/mucoid, tenesmus + LLQ pain, systemic symptoms.
    • Site of involvement is the colon. Common causes are Shigella, Campylobacter, EHEC, Entamoeba histolytica
    • Positive fecal WBC
  • Importance of vomiting: Usually indicates the ingestion of a pre-formed toxin or a viral infection. Examples:
    • Staph aureus
    • B. cereus
    • Norovirus
    • Certain parasites


  • Norovirus (very common)
  • Rotavirus, enteric adenovirus, astrovirus (usually in immunocompromised adults)
  • diff (can be bloody/inflammatory)
    • Nosocomial vs community acquired
  • Clostridium perfringens (2nd most common cause of foodborne bacterial infection)
    • Associated with outbreaks in restaurants and catering facilities
    • Usually mild symptoms.
    • Associated with improperly cooked or stored meat.
    • Self-limited, supportive care often suffices
  • Enterotoxigenic E.coli (ETEC): AKA traveler’s diarrhea
    • Cruise ships, foreign countries, fecal contimation or food or water from an infected person.
  • Giardia lamblia:
    • Water & food borne outbreaks
    • Sx: 7-14 days incubation post exposure.
    • Presentation: Foul smelly stools, cramps, bloating.
    • Tx: Supportive + Metronidazole, Tinidazole, albendazole
  • Cryptosporadium
    • One of the most common parasitic foodborne diarrhea
    • Endemic in cattle, usually transmitted via infected animal or person. Food/water borne outbreaks also common.
    • Presentation: Severe, dehydrating watery diarrhea but self-limited in immunocompetent hosts.
    • Immunocompromised: More severe
  • Other bacterial
    • Staph aureus, Bacillus cereus: enterotoxins, acute diarrhea + vomiting
    • Listeria monocytogenes: Can cause systemic symptoms/spread
    • Cyclospora: Associated with sporadic outbreaks due to imported raspberries and basil.
    • Aeromonas: Distributed in watery environments, suspect if contact with fresh or brackish water.
  • Other viral: Hepatitis A

Inflammatory: bloody or mucoid diarrhea, with associated fever, abd pain. Presence of inflammatory cells in the stool. More likely bacterial.

  • Salmonella: Nontyphoidal, leading cause of acute inflammatory diarrhea
    • Association: Poultry, eggs, milk products, animal contacts
    • Incubation: 8 – 72 hours
    • Presentation: diarrhea is usually non-bloody, N/V, fever.
  • Campylobacter
    • Undercooked poultry
    • Watery or hemorrhagic diarrhea, 2-5 days after exposure
    • Association: Guillain-Barre, reactive arthritis
  • Shigella: Dysenteric diarrhea
    • Colonic infection, person to person or fecal oral transmission.
    • Mucoid or bloody diarrhea, 3-7 days after exposure.
  • EHEC: Enterhemorrhagic E.coli
    • Association: HUS
    • Presentation: Watery/progressively bloody diarrhea, 3-4 days post exposure, abd pain + fever.
  • Yersinia
    • Uncommon, can be transmitted via undercooked pork, unpasteurized milk, fecally contaminated water. 1-14 days after exposure
    • Associated with concurrent pharyngitis.
  • Others: Entamoeba histolytica, noncholera vibrios, CMV, HSV
    • CMV & HSV: Dx has to be confirmed by biopsy. Suspect these in immunocompromised patients.

Neutropenia and GI symptoms

Neutropenic enterocolitis (typhilitis), cytotoxic agent-related diarrhea, any viral/bacterial infection, but for typhilitis specifically:


  • Associated with hematologic malignancies or ingestion of food contaminated with C. perfringens
  • Pre-existing bowel wall abnormalities increases risk (i.e. diverticulitis, tumor, previous surgery).


  • Infection of the bowel wall, usually the cecum but can involve ascending colon & ileum, leading to tissue necrosis


  • Neutropenic
  • Fever, mean of 3 weeks after cytotoxic chemo
  • Abd pain, distension, N/V, watery/bloody diarrhea
  • Usually RLQ pain, can mimic appendicitis.


  • CT


  • 4th gen cephalosporins i.e. cefepime + Flagyl, surgery is generally avoid but indicated if e/o perforation


  • 50% mortality



  • Most common viral cause of gastroenteritis worldwide, all age range affected
  • 19-21 million cases every year in the US
  • Unclear reason, peak incidence during winter months.
  • Food born outbreaks is common: leafy greens, fruits, shell fish.


  • Fecal oral transmission, RNA virus
  • Different genotypes exist with further sub-groups, tend to have a preference for certain blood type.
  • Incubation: 24-48 hours, affects the small intestines
  • Very infectious, can cause full blown infection even if exposed to a small amount (< 100 viral particles)
  • Extremely stable in the environment, resists freezing or heating up to 60 degrees C, disinfection requires chlorine or EtOH
  • Viral shedding is max over the first 24-48 hours, and pts can continue to shed for up to weeks


  • Duration: 48-72 hours
  • Watery diarrhea, N/V, abd pain.
  • Vomiting usually prominent
  • Usually self-limiting but can be severe in immunocompromised patients


  • Stool PCR


  • Supportive
  • Contact plus isolation
  • Notify infection control (contact plus isolation)
  • If you have been exposed to someone with norovirus and you are symptomatic, PLEASE CALL IN SICK since this illness is highly contagious. Notify us and employee health. You have to be asymptomatic for at least 48 hours, and you have to be cleared by employee health, prior to returning to work.

Necrotizing Fasciitis & Ludwig’s Angina

Thanks to Joe for presenting the case of an elderly man with no known medical history who presented with acute AMS, found to have L facial swelling and crepitus, eventually diagnosed with necrotizing Ludwig’s angina!

Clinical Pearls

  • Necrotizing fasciitis (NF) is a surgical diagnosis and involves infection of muscle and subcutaneous fat.
  • CT is a useful tool to help with diagnosis and in one case series had a 100% sensitivity and >80% specificity for diagnosing NF.
  • LRINEC or Laboratory Risk Indicator for NF is a lab-based risk assessment tool to help risk stratify patients with possible NF.  It has a sensitivity of 80% and specificity of 67%.  It should NOT supplant your clinical judgement.
  • Ludwig’s angina refers to any infection of the submandibular space (not just NF).  Normally the treatment for Ludwig’s angina is antibiotics.  In the case of NF, urgent surgical debridement is necessary.  In spite of antibiotics and debridement, head and neck necrotizing infections are associated with a high mortality rate (~40%).
    • In patients with Ludwig’s angina, always involve anesthesia AND ENT to help secure airway. Oral intubation is associated with higher rates of laryngospasm in these patients so oftentimes nasal intubation is preferred.

Deep neck infections:


Necrotizing fasciitis

  • Background
    • Infection of deep tissues, specifically muscle fascia and subcutaneous fat.
    • Two main types
      • Type 1: polymicrobial
        • More common in elderly and those with significant comorbidities including diabetes, immunocompromised states, PVD, etc.
        • Blood cultures are positive in ~20% of patients.
      • Type 2: monomicrobial (usually GAS but can be other beta-hemolytic strep and MRSA)
        • Can be seen in any age group and without any underlying disease.
  • Clinical manifestations
    • Remember that you do not need to have a penetrating injury for NF.  Oftentimes, blunt trauma is the preceding history and overlying tissue does not show any signs of infection, leading to the “pain out of proportion to exam” finding.
    • Systemic signs of toxicity (including hypotension and shock), rapid progression, crepitus.
    • LRINEC or the Laboratory Risk Indicator for NF is a lab-based risk assessment tool to help risk stratify patients with possible NF.
      • It has a sensitivity of 80% and specificity of 67%.  It should NOT supplant your clinical judgement.
    • CT scan is highly sensitive (100% in one case series of 67 patients) and specific for differentiating NF from celllulitis.
    • Ultimately, NF is a surgical diagnosis so consult surgery early if you are concerned about the diagnosis and before waiting for imaging in an unstable patient!
  • Treatment
    • Early surgical intervention and debridement
    • Empiric antibiotics
      • Beta lactam/beta lactamase inhibitor or carbapenem PLUS
      • vancomycin or other similar drug for MRSA coverage PLUS
      • clindamycin
        • Eagle effect: at high bacterial loads, there is reduced efficacy of beta-lactam antibiotics for strep pyogenes infections due to reduced exposure of penicillin binding protein on the bacteria.  Clindamycin works better in these situations and does not rely on the penicillin binding protein site.
        • Toxin neutralization: clindamycin has the ability to suppress synthesis of bacterial toxins that cause systemic symptoms in patients with NF.
    • Other therapies such as hyperbaric oxygen and IVIG have not shown reliable evidence of benefit in studies and are not currently recommended by the IDSA.
  • Prognosis
    • Mortality is high even with appropriate treatment (up to 45%).


Refer to this amazing review by NEJM for more info on NF.


Acute Rheumatic Fever

Today, we talked about the very interesting case of a middle-aged man who presented with acute migrating oligoarthritis, found to be febrile with an inflammatory synovial fluid and elevated ASO titers consistent with acute rheumatic fever!

Clinical Pearls

  • Nonsuppurative manifestations of GAS infection include acute rheumatic fever (ARF), acute GN, and Scarlet fever.
  • Use the modified Jones Criteria to help you diagnose ARF and treat early if high suspicion for the disease (do not wait for titers to come back).
  • Late complications of ARF include rheumatic heart disease (10-20 years after infection) and Jaccoud arthropathy.
  • Treatment of ARF involves NSAIDs for arthritis, PCN G IM x 1 dose for acute presentation and then monthly for prophylaxis, and patient education about oral hygiene to prevent endocarditis and need for prophylaxis before invasive procedures.

Differential diagnosis for a migratory arthritis

  • Rheumatic fever
  • Infective endocarditis
  • Vasculitis (IgA, cryo, ANCA associated)
  • SLE 
  • Acute leukemia
  • Serum sickness
  • Viral arthritis
  • Bacteremia (staph, strep, mening/gonococcal)
  • Pulmonary infections (mycoplasma, histoplasma)
  • Lyme
  • Whipple’s

Nonsuppurative complications of GAS infection

  • ARF
  • Scarlet fever
  • Acute GN

Rheumatic fever 

  • Nonsuppurative sequela that occurs 2-4 weeks after GAS pharyngitis
  • Epi
    • More common in children 5-15 years of age
    • More common in resource limited settings
  • Pathogenesis:
    • Poorly understood, ?molecular mimicry
  • Clinical manifestations:
    • Two primary manifestations of disease

Two manifestations of ARF

(Table above from UpToDate)

  • Late sequelae
    • Rheumatic heart disease (10-20 years after infection), primary involves the mitral valve >aortic valve.
      • Leading cause of cardiovascular death in the first 5 decades of life in resource limited settings
    • Jaccoud arthropathy
  • Diagnosis:
    • Revised Jones criteria (joint and cardiac manifestations can only be counted once).
      • Major
        • Carditis and valvulitis (clinical or subclinical) – 50-70%
          • Usually pancarditis. Valvulitis especially of mitral and aortic valves, shown as regurg on echo.
          • Carey Coombs murmur: short mid-diastolic murmur heard loudest at the apex
        • Arthritis (migratory, involving large joints) – 35-66%, earliest symptom
          • Several joints affected in quick succession, each inflamed for a day or two to one week. Most common are knees, ankles, elbows, and wrists.
        • CNS involvement (Sydenham chorea) – 10-30%
        • Subcutaneous nodules – 0-10%
        • Erythema marginatum – <6% 
      • Minor
        • Arthralgia
        • Fever >38.5
        • Elevated acute phase reactants (ESR, CRP)
        • Prolonged PR interval on EKG
      • Diagnosis requires evidence of prior GAS infection plus:
        • 2 major OR
        • 1 major + 2 minor criteria OR
        • 3 minor criteria (only if patient has history of prior episode of ARF)
      • In a high prevalence setting, slightly modified criteria are used.
    • Labs:
      • Prior GAS infection through either
        • Throat culture
        • Positive rapid strep antigen test
        • Elevated or rising ASO titers
      • Treatment
        • Goals
          • Symptomatic relief of acute disease manifestations
            • Arthritis: NSAIDs
            • Carditis: if severe, heart failure treatments
          • Eradication of GAS
            • IM PCN G benzathine x 1
            • Contacts (throat culture test and treat if positive)
          • Ppx against future GAS infection to prevent progression of cardiac disease
            • PCN G IM once a month
            • For 5 years or until 21 years of age (whichever is longer)
            • If ARF with carditis and residual heart disease
              • 10 years or until 40 years, sometimes even lifelong
            • Education
              • Oral health
              • Ppx before any invasive procedures

Stroke from CNS TB induced vasculitis!

Thanks to Katie for presenting the interesting case of a young man with history of disseminated TB with TB meningitis and hydrocephalus requiring VP shunts, admitted for acute LUE weakness, L homonymous hemianopsia, and memory impairment, found to have acute strokes in multiple vascular territories due to TB related CNS vasculitis!

Clinical Pearls

  • Remember that arterial dissection is the most common cause of stroke in a young patient.
  • CNS vasculitis can be primary or secondary to a systemic illness.  It typically presents with infarcts in multiple vascular territories.  Treatment involves immunosuppression with high dose steroids + cytoxan/rituxan.
  • CNS vasculitis is the most common cause of severe neurologic deficit in patients with TB meningitis.
  • Vasculitis in CNS TB is the result of a hypersensitivity reaction to proteins released from the bacteria.
  • TB meningitis requires an extended course of anti-TB treatment, generally up to 1 year or more.  Serial LPs are obtained to monitor adequate response to therapy.

Etiologies of stroke in a young adult


Three main manifestations:

  1. TB meningitis (most common presentation in low incidence settings like the US)
  2. Intracranial tuberculoma
  3. Spinal tuberculous arachnoiditis

Spillage of tubercular protein into the subarachnoid space results in an intense hypersensitivity reaction and inflammation resulting in

  • Proliferative arachnoiditis (fibrous mass encasing cranial nerves and vessels adjacent to it)
  • Vasculitis with resultant aneurysm, thrombosis, and infarction
  • Communicating hydrocephalus 

TB Meningitis

  • 1% of all TB cases, 5% of all extrapulmonary TB cases
  • 15-40% mortality rate
  • Clinical manifestations
    • 3 stages:
      • Prodromal phase: malaise, headache, low grade fever, personality changes
      • Meningitic phase: meningismus, headache, vomiting, lethargy, confusion, CNS signs, some motor deficits
      • Paralytic phase: stupor, coma, seizures, hemiparesis (death within 5-8 weeks)
  • Diagnosis:
    • Characteristic CSF findings of low glucose, elevated protein, lymphocytic pleocytosis 
    • CSF AFB smear and culture: in general, a minimum of 3 serial LPs should be performed, as diagnostic yield increases f
    • Nucleic acid tests: Xpert MTB/RIF assay should be submitted in the setting of high clinical suspicion and negative AFB staining.
  • Treatment
    • Intensive phase (2 months): four drugs RIPE. Ethambutol has poor CNS penetration so some use fluoroquinolones instead.
    • Continuation phase (7-10 months)
    • Steroids
      • A review of 9 trials on 1337 patients found that use of steroids reduced death and disability by ~25%.
      • Benefit higher if started earlier in disease process.
      • Treat for 8 weeks, slow taper.
    • Stroke
      • A retrospective study in Stroke 2018 on patients with TB meningitis found that those >40, with concurrent HTN, dysplipidemia, and DM were more likely to have this complication. Some small case series showing benefit in reducing future strokes with the use of Aspirin.
      • No role for tPA.

Neurosyphilis? Wait… reactive arthritis!

Thanks to Tim for presenting the interesting case of a middle-aged man with h/o inadequately treated syphilis who presented with neck stiffness worse in the mornings, back pain, and blurry vision, admitted for presumed neurosyphilis.  Exam revealed inflammation of T2/T3 joints, L SI joint tenderness, and an inflamed R foot with dactylitis of the 3rd and 4th digits.  Further history revealed a recent gonorrhea/chlamydia for which he was treated and HLA B27 positivity consistent with reactive arthritis!  He was started on NSAIDs with significant improvement of symptoms.

Clinical Pearls:

  • Neurosyphilis is most commonly seen in HIV positive patients and can present at any time after infection.
  • Early neurosyphilis occurs within the first year after infection and involves the CNS, meninges, and vasculature
    • Neurosyphilis presents with posterior uveitis or pan-uveitis whereas reactive arthritis presents with anterior uveitis
  • Late neurosyphilis occurs >10 years after infection and involves the brain and spinal cord parenchyma
  • The four main spondyloarthropathies are ankylosing spondylitis, psoriatic arthritis, reactive arthritis, and IBD-related arthritis.
  • The genital pathogen most commonly associated with reactive arthritis is chlamydia trachomatis.
    • HLA B27 is positive in 30-50% of patients
    • Mainstay of treatment is NSAIDs
    • Disease typically lasts 3-5 months.



Clinical manifestations and treatment of different stages of syphilis

Neurosyphilis manifestations

  • Refer to this prior post
  • Early (w/n first year of infection)
    • CSF, meninges, vasculature
    • Symptomatic meningitis
    • Ocular syphilis (posterior uveitis, panuveitis)
    • Meningovascular syphilis
      • Arteritis of any sized vessel which can lead tostroke or spinal cord infarction
  • Late
    • Brain and spinal cord parenchyma
      • General paresis (10-25 years after initialinfection)
        • Progressive dementia
        • Psychiatric symptoms
      • Tabes dorsalis (>20 years after initialinfection)
        • CSF may be completely normal
        • Affects dorsal columns
        • Symptoms
          • Sensory ataxia
          • Argyll-Robertson pupil
          • Lancinating pains
  • Diagnosis
    • Non-treponemal tests (poor sensitivity but highspecificity)
      • VDRL
      • RPR
    • Treponemal tests
      • FTA-ABS
      • Syphilis EIA
    • In an HIV negative patient with suspectedneurosyphilis and a non-reactive CSF-VDRL, one can establish the diagnosis with
      • CSF lymphocytes >5 cells/microL
      • CSF protein concentration >45

Reactive Arthritis

  • Epimiology
    • Young adults, M:F equal
  • Typically follows GI or urogenital infections (several days to weeks after infection)
    • Chlamydia trachomatis (most common genital infection associated)
    • Yersinia
    • Salmonella
    • Shigella
    • Campylobacter
    • E coli
    • C diff
    • Chlamydia pneumoniae
  • Manifestations
    • Mono- or oligoarticular pattern of arthritis,often involving the lower extremities, sometimes associated with dactylitis and enthesitis
    • The triad of arthritis, urethritis, andconjunctivitis is only present in a subset of patients (formerly called Reiter’s syndrome)
    • Ocular manifestions: conjunctivitis, less frequently anterior uveitis, episcleritis, and keratitis.
    • Other: 
      • Skin: keratoderma blennorhagica, erythema nodosum
      • Circinate balanitis 
      • Nail changes resembling psoriatic arthritis
  • Lab
    • E/o of antecedent or concomitant infection
    • Elevated acute phase reactants
    • Positive HLA-B27 (present in 30-50% of patients)
    • Inflammatory synovitis
    • Imaging consistent with enthesitis or arthritis
  • Treatment
    1. Treat any ongoing concurrent infection
    2. NSAIDs (first line)
    3. Steroids (if refractory to NSAIDs)
    4. DMARDS (for chronic reactive arthritis)
    5. Anti-TNF (last resort)
  • Prognosis
    • Duration is typically 3-5 months
    • >6 months duration is considered chronic reactive arthritis
    • Most remit completely or have little active disease w/n 6-12 months after presentation
    • 15-20% may experience more chronic persistent arthritis

Spontaneous Bacterial Peritonitis secondary to… Acinetobacter? 11/14/2018

Our doctor-in-training Jacqueline presented a middle man with infrequent medical care, with a history of heavy alcohol use, who presents with generalized swelling and anorexia. He was septic on presentation with a distended abdomen. Ascitic fluid anlysis was concerning for bacterial peritonitis, and blood cultures (4/4 bottles) were positive for acinetobacter with OXA resistance marker!

Spontaneous bacterial peritonitis

Important to distinguish between Spontaneous bacterial peritonitis (SBP) vs Secondary bacterial peritonitis (also SBP but for the sake of clarity, SBP from this point on will refer to spontaneous bacterial peritonitis)

  • Secondary: Bacterial peritonitis secondary to something else besides spontaneous, i.e. bowel perforation, surgery.
    • 100% mortality without surgical intervention. Surgical risk is high but patient mortality is almost guaranteed without surgery!
    • If Spontaneous BP, mortality can approach 80% with abdominal surgery.
  • Diagnosis: history, fluid analysis
  • Cultures from peritoneal fluid usually polymicrobial (gut flora)
  • Tertiary bacterial peritonitis: Persistence of peritonitis or abscess following adequate treatment of primary or secondary peritonitis


  • Pts with cirrhotic ascites, suspect SBP in all these patients, and also pts with ascites suffering from a GIB.
  • Organisms: E.coli, Klebsiella, strep pneumo are most common, usually single organism
  • Less common: Acinetobacter, pseudomonas, proteus
  • If polymicrobial of anaerobes, suspect secondary bacterial peritonitis
  • Rarely fungal but they have been described, poor prognosis.


  • S/S of ascites
  • May have fever, malaise, encephalopathy, decompensated liver cirrhosis, peritoneal signs sometimes.
  • Frequently an instigator for hepatorenal syndrome in cirrhotic patients.


  • PMN > 250 cells/mL
  • Positive cultures/Gram-stain
  • Absence of secondary causes


  • Antibiotics:
    • Cefotaxime 2g Q8H
    • Ceftriaxone once daily is an alterative with some evidence trending toward improved survival and less ICU stay with 2g daily dosing vs 1g.
    • Cefepime 1-2g Q8H is an alternative as well esp for resistant pathogens.
    • Fluoroquinolones: Consider alternative if pt already on a quinolone for prophylaxis prior to developing SBP. Can use Cipro, Levo, or Moxi.
    • Carbapenems
    • Beta lactam/Beta lactamase inhibitors i.e. Zosyn
    • Duration: At least 5 days
  • Albumin: Recommended, RCT published in NEJM in 1999 established the administration of albumin decreases the incidence of renal failure with albumin + antibiotics as well as decrease in mortality.
    • Patients in the study who were most likely to benefit from albumin had:
      • Bili > 4
      • Cr > 1
      • BUN > 30
    • 1.5g albumin /kg on day 1, the 1.0g/kg on day 3. Dose limited to max of 100g
  • HRS (Hepatorenal syndrome): 1.0g/kg albumin days 1 & 2 and see if renal function improves (albumin challenge)


  • Renal failure can be seen in 30-40% of patients with SBP
  • Prognosis tends to be poor once HRS sets in
  • HRS
    • Type 1: Rapid progressive decline, 50% 1 month mortality
    • Type 2: More subacute/chronic, not associated with an inciting event, median survival 6 months


  • Primary
    • Cirrhotics presenting with GIB should get primary prophylaxis, total duration of therapy x 7 days
    • Ascitic protein < 1.0 g/dL can also be considered (RCT published in Journal of Hepatology in 2008)
    • Ascitic protein <1 and Childs Pugh > 9 or T.bili > 3 or renal dysfunction: can also consider long-term primary prophylaxis, based on an RCT from Gastroenterology in 2007, drug of study was norfloxacin.
  • Secondary
    • Indicated after first episode of SBP, one year recurrence rate of 40-70%, mortality rate of 50-70%
    • Meds: Norfloxacin or cipro daily, Bactrim also an equivocal alternative
    • Life-long or until transplant

Please refer to this article for an overview of SBP.



  • Nosocomial, ICU
  • Tropical/humid environments
  • Water and soil
  • Certain strains can survive in a desiccated environment for weeks.


  • Most commonly in ventilator associated pneumonia and blood stream infection (1.5% – 2.4%)
  • Others: Central line, catheters, surgical site infection
  • Can be contamination, pts and health care workers can be colonized
  • Can also present as endocarditis or meningitis or ocular infection (contact lens)
  • Peritonitis secondary to acinetobacter usually more common in peritoneal dialysis patients.

Risk Factors

  • Prior antibiotics, especially beta lactams, carbapenems, fluoroquinolones
  • Presence of catheters, ICU
  • PD (especially in setting of peritonitis secondary to actinobacteria)
  • Trauma, burn, immunosuppression


  • Increasingly resistant, both acquired and inherent
  • ESBL phenotype also emerging


  • 1st line: cephalosporin (ceftaz, cefepime), beta-lactam/beta lactamase inhibitor, carbapenems are highly effective, ampicillin0sulbactam is also very effective.
  • Sometimes combination therapy is used i.e. with a fluoroquinolone or aminoglycoside due to concerns of emerging and acquired resistance but limited data on combo therapy vs emergences of resistance or whether clinical outcome is improved.
  • Other possible options: minocycline, tigecycline, polymyxins


  • 2x more likely to die from a carbapenem resistant strain