Day #243 Atrial Fibrillation and Congestive Heart Failure

We've previously discussed atrial fibrillation and the urgent management thereof here.

This patient was on digoxin, and was not toxic. I've discussed digoxin toxicity and the use of digoxin in CHF here.

I have discussed CHF here and some of the causes of cardiomyopathy here. An article on cardiomyopathy taxonomy is available here.

Day #242 - Syncope

The approach to syncope involves an attempt to determine the etiology on the basis of the history, physical exam, and investigations. A guideline is available here.

Approximately 20% of the population, at any age, will have syncope.

• Cardiogenic Cause (Highest 1yr mortality)
  
  • Structural - AS, HOCM, Severe MS, Myxoma, Other
  • Arrythmogenic -
    
    • Tachyarrythmia: Atrial fibrillation, VT/VF, other
    • Bradyarrythmia: Sinus arrest, "Sick Sinus Syndrome", AV Block
  • Ischemia/Aortic Dissection
  • Tamponade
    
  • Pulmonary Embolism/Pulmonary Hypertension
    
• Neurogenic/Neurocardiogenic Cause
  
  • Vagally mediated - vasovagal, defication, micturition, cough/sneeze
  • Orthostasis/Hypovolemia
    
    • Drug induced (i.e. diuretics/vasodilators)
    • Disease mediated (i.e. autonomic dysfunction from DM, or Parkinson's)
    • Hypovolemia from any cause
      
  • Carotid Sinus Hypersensitivity
  • Choking on a pretzel...
    
• Not Syncope
  
  • Seizure
  • Pseudosyncope

Scenario Rounds -- Status Epilepticus

See here.

Day #239 - Clostridium Difficile (C. Diff)

Today we discussed a case of severe Clostridium difficile associated diarrhea. I have previously blogged about the differential of colitis here.

There is a general review of C. difficile available from last week's JAMA. I prefer these two (#1 and #2) editorials by John Bartlett.

A full suppliment to the journal Clinical Infectious Diseases was devoted to C. difficile in January 2008 and it is very good.

Diagnosis of C. Diff

Microbiology

• At our hospital, the C. diff toxin assay (EIA) detects toxins A and B and has ~70% sensitivityon a single test, with ~90-95% sensitivity on three tests. The specificity greater than 95%.
• The most sensitive assay is the test for cytopathic effect, which is not available
• You can also culture Clostridium difficile from the stool, although most laboratories no longer do this, and just because you grow it does not necessarily mean that it is causing disease

CT Scan

• May show thickening of the bowel wall, colitis, ileus. "Double Halo" and "Accordian Signs"
  

Sigmoid/Colonoscopy

• May see pseudomembranes diagnostic of pseudomembranous colitis

Treatment of First Episode

• If possible stop offending antibiotics
• Mild/Moderate Disease
  
  • Metronidazole OR Vancomycin (PO) duration 10-14d
    
• Severe Disease
  
  • Defined as:
    
    • Two of (Age above 60, Febrile, WBC above 15, Albumin below 25)
      
    • OR hypotension/shock or Cr greater than 1.5x normal, or toxic megacolon, peritoneal signs, perforated bowel
      
  • Infectious Disease +/- General Surgery Consultation
  • ICU Consult for patients with hemodynamic comprimise
    
  • Vancomycin (PO) unless severe illeus, then Metronidazole (IV) duration 10-14d
    

Relapse

• First relapse --> can repeat last treatment depending on severity
• Second relapse --> vancomycin taper (see JAMA article). ID consult.
  

Day #238 - Cirrhosis and Pancytopenia

Today we discussed a case of presumed cirrhosis and pancytopenia from chronic ETOH over-use.

I have previously blogged about cirrhosis (including management of complications, approach to ascites/SBP) here and here.

The Physical Exam for ascites is reviewed here. How-to paracentesis here.

I have also blogged about the approach to macrocytic anemia here.

Day #237 - Hepatoma and HCC

Hepatocellular carcinoma is a highly vascular primary cancer of the liver which often arises in the context of underlying cirrhosis and ongoing/chronic liver inflammation caused by viral hepatitis (B and C). In general the risk in cirrhosis is approximately 3% per year.



The diagnosis is often made based on the radiographic appearance and clinical context. From uptodate: "If the lesion is hypervascular, has increased T2 signal intensity, demonstrates venous invasion, or is associated with an elevated AFP, the diagnosis is almost certainly HCC."

There are several staging systems. One useful system is the CLIP score:

• Underlying liver disease:
  
  • Child-Pugh A = 0, B=1, C=2
• Size and extent of tumour
  
  • Uninodular and not extending more than 50% =0
  • Multinodular and not extending more than 50% =1
  • Massive or extending more than 50% = 2
• AFP greater than 400 = 1
• Portal vein thrombus =1

CLIP: 0, 1, 2, 3, 4, 5/6 has associated median survival of 31, 27, 13, 8, and 2 months respectively.

There can be several paraneoplastic syndromes associated with HCC:

• polycythemia (related to EPO)
• hypercalcemia
• hypoglycemia
• chronic watery diarrhea
  

Treatment:

• In general surgical resection is limited to patients with good hepatic reserve (CPA), absence of metastases, absence of invasion of major vascular studies.
  
• Surgery is generally more successful in lesions less than 5cm
• Transplantation of the liver can be an option in patients with inadequate reserve or otherwise unresectable lesions. This really is only an option for lesions less than 3-5cm and solitary or less than three lesions.

• Radiofrequency ablation (RFA) is an option for lesions less than 4-5 centimeters who are otherwise deemed unresectable.
• TACE (transarterial chemoembolization) is an option for unresectable lesions in the absence of portal vein thrombosis. It is relatively contraindicated in tumours making up more than 50% of the liver, heart failure, renal failure, ascites, GI bleeding or thrombocytopenia.
  

There was a recent publication on the use of tyrosine kinase inhibitors in the treatment of advanced HCC showing improved survival.

I have previously blogged about hepatitis B, the most common worldwide cause of hepatoma, here.

Day #236 - Pneumocystis (PCP) x 3

I've previously blogged about PCP here.

We discussed opportunistic infections in HIV here.

A previous talk I've given on HIV is available here.