Second week is almost over - it's been interesting. This week he started his inpatient rounds at the hospital, so we've been going to the hospital in the mornings and rounding on whichever of his patients happen to be hospitalized or cases that require his consultation. Had a case of mesenteric venous thrombosis, which apparently is pretty uncommon so they have been doing a full coagulation disorder work up - protein C, protein S, antithrombin III, antiphospholipid antibodies, the works. More and more data have been coming out suggesting that HIV infection in itself produces a hypercoagulable state, and thus people are more likely to suffer a thrombosis or a stroke simply because they are HIV positive. It is not precisely known why, but they are looking into it.
There have been a few altered mental status patients as well, and one who has a recurrence of toxoplasmosis in addition to esophageal candidiasis and other things. Been seeing lots of patients with lipodystrophy, or abnormal lipid deposition due to the HIV medications. A lot of the medications cause fat deposition on the abdomen and the neck, and sucks fat away from the arms, legs, buttocks, and cheeks, so they can end up with a very odd body habitus. A lot of them come in for problems unrelated to the HIV, such as poorly controlled diabetes, or joint pain. The doctor I am shadowing spends 45 minutes or more with most of his patients because he goes through a list of 20 issues, some of them pretty minor. He is definitely very comprehensive - takes his time, makes sure to ask about every aspect of the patient's life. Being a primary care physician for so many patients as well as a specialist looks quite challenging - especially since they don't have medical records so he still does a lot of writing up of charts and has to go to the hospital to sign for things.
On Wednesday morning I got to attend HIV grand rounds at San Francisco General Hospital - the doctor I am shadowing as well as a UCSF HIV pathology researcher/lecturer and the Kaiser Permanente HIV management physician were on a panel to discuss some interesting cases and do some Q&A. It was good that I had had a lot of discussions with the doctor about HIV before the panel, because otherwise some things would have been harder to follow. At the end of this rotation I will definitely know all the combination therapies, as well as which drugs are NRTIs, NNRTIs, and PIs. It's gotten easier already.
Two things I have learned about on this rotation are HIV strain reversion to wild type, and protease inhibitor "boosting". Because patients go on and off drug regimens when they gain and lose insurance, they can develop resistant strains of HIV - however, some of these mutations that develop decrease the fitness of the virus (similar to sickle cell increasing resistance to malaria but decreasing overall fitness/survival in humans). Anyhow, while there are drugs exerting selection pressure, the mutants can survive and overpopulate the wild type, but when the drugs are discontinued the mutants die off and the wild type becomes the dominant strain. Sometimes the mutant type is no longer replicating so genotype tests will not show any resistance patterns. However, because HIV is a drug that integrates and hides in host cell DNA, those resistant mutants are usually still hiding somewhere in a cell in the body and can emerge again if you re-start therapy with the drug that selected for them in the first place. This can make treatment a challenge. As far as protease boosting, we were taught a list of 'protease inhibitors.' One of the protease inhibitors is ritonavir, which I thought was like the other protease inhibitors, but turns out that it is not particularly effective at suppressing the virus, but acts to improve the effectiveness of the other protease inhibitors such as darunavir or fosamprenavir. So that was useful to know - I was wondering why I kept seeing 3 drug regimens that had four drugs listed (including ritonavir, which they don't count as one of the 3 drugs).
Anyhow, one more day tomorrow - just hospital rounds in the morning - and then a 3 day weekend!