Day #126 - Hepatitis B

Today we discussed a patient with acute hepatitis on the backgroud of hepatitis B chronic infection. I have previously discussed acute hepatitis, cirrhosis and complications thereof.

I wanted to talk about hepatitis B -- Firstly, this is a great review article and so is this.

Secondly - Serologies:

• Early in infection you have the production of Hepatitis B Surface Antigen and Hepatitis B Envelope Antigen which represents active infection
• The you develop hepatitis B core IgM then core IgG. These antibodies are not protective
• If you are going to clear your infection you will next develop anti-hepatitis B-EAg antibodies, clear your E antigen and then start to clear your S-Antigen
• You then make hepatitis B surface antibodies
• There can be a window period in between clearing the S-Ag and developing the anti-HepB surface antibody where the only way you will know if they are infected is by the core antibody.

An immunized person will only have hepatitis B surface antibody

A natural, but cleared infection will have positive HepB surface antibody and core antibody and no surface antigen

A patient with chronic active hepatitis will have core antibody and in most cases hepatitis B surface antigen. They may also have E antigen (or E antibody). They will not have surface antibody.

For chronic carriers treatment depends on a number of factors -- this table provides an excellent summary:

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Note that I link to a lot of NEJM articles. This is my preferred journal. Those of you with a U of T library account have NEJM access via e-journal search in the gerstein library website. We pay for an institutional license @ U of T which you can access at home and there is a licence here at the hospital.

Those of you who would like their own subscription (b/c above don't work) can obtain one here ($~60/year for electronic only ~ $150 for print copy too)

Day #124 - Pretibial Septic Bursitis

Today's case was of a painter, who did a lot of work on his hands and knees, presenting with acute onset knee pain. We discussed the differential diagnosis in detail and then focused on septic arthritis. I have previously blogged about this here and had linked to an excellent article that I recommend you reading.

In this case, the diagnosis was pretibial septic bursitis, which can mimic septic arthritis and is commonly seen in people who do labor on their hands and knees and is associated with minor traumas. The most common infectious aetiology is stapylococcus aureus.

Day #119 - Adult Onset Still's Disease

This was a great case which the discussant enjoyed taking us through. I have previously blogged about fever of unknown origin here, here and here.

There was a previous special guest blog about FUO here.

Here are articles suggested by the discussant on rheumatologic causes of FUO, Adult Onset Still's Disease, and the use of IL-1 antagonists in the treatment of Still's.

Here is another review on Stills.

Day #118 - Probable Leptospirosis

Today we heard a case of a returning traveller who suffered complete cardiorespiratory collapse as part of a sepsis syndrome. In this syndrome the patient was hypotensive requiring inopressors, hypoxemic/hypercapnic requiring ventillation, coagulopathic with a microangiopathic hemolytic anemia (see TTP blog and previous anemia/thrombocytopenia blogs) from DIC, and in acute renal failure. In the context of this illness he suffered either myocarditis or a myocardial infarction related to hypoperfusion.

This was as sick as anyone can be and survive and it is a testiment to our critical care system that he did indeed survive.

We spent time discussing the approach to diarrhea, which was his initial presenting symptom.

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We then defined sepsis

SIRS Criteria:

• Fever or hypothermia
  
• WBC >12,000 or less than 4,000
• HR >90
• RR >20

Sepsis = 2 or more SIRS criteria of presumed infective etiology
Severe sepsis includes sepsis with end organ dysfunction or lactate >4
Septic shock includes severe sepsis with refractory hypotension requiring inopressors

We then talked about the approach to early goal directed therapy in sepsis.

In this case, I believe early appropriate antibiotic therapy would include:

• Vancomycin (in case of community associated MRSA in a young man)
• Meropenem (to cover streptococcus, gram negatives including ESBL/drug resistant)
• Doxycycline to cover leptospirosis

In general, in a critically ill patient like this, I will draw cultures and then use very broad spectrum coverage empirically with a plan to de-escallate when culture results are available

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The etiology in this case is unclear but I wonder about leptospirosis. I didn't really want to talk about leptospirosis in detail during the case presentation.... This is the case of leptospirosis in NEJM that I elluded to.

I have provided you with a copy of a talk I once gave on leptospirosis here.

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Free tidbits:

Here is an article on fever in the returning traveller
A good review of typhoid fever is here.