An ongoing dialogue on HIV/AIDS, infectious diseases,
February 25th, 2020
First Week on Service, with One-a-Day ID Learning Units
There is almost always something to be learned from every new patient.
It might be buried somewhere in the history, or the physical, or the lab tests, or the micro, or the imaging — but the odds are excellent that, with enough rumination, you’ll find it.
I can’t remember now who taught me this important fact, or even if it was ever explicitly stated to me. Quite possibly it was just implied — or personified in action — by some really smart, impressive clinical mentor. Someone skilled in finding that nugget of learning in every case.
It might have been my legendary residency program director; or the World’s Greatest Chief Medical Resident (I’m still missing her, sadly); or the brilliant Chief of ID during my fellowship; or the most intuitive ID clinician on the planet.
(FYI, that last guy remains an invaluable resource on tough cases.)
Regardless, these ID Learning Units are out there. And here are seven — one-a-day — from my first week on the inpatient ID consult service:
1. Cystic neutrophilic granulomatous mastitis. You’ll have an “a-ha” moment the first time you see this strange and challenging entity.
Day #1: Cystic neutrophilic granulomatous mastitis (CNGM) is a chronic inflammatory process, associated with corynebacterium spp. (Causal?) Optimal management remains unclear–generally involves combination of abx and corticosteroids. @Yijia_89 https://t.co/RjeerNHSb6
— Paul Sax (@PaulSaxMD) February 19, 2020
2. Consider pulmonary arteriovenous malformations when encountering a brain abscess, especially if there are no other obvious risk factors.
Day #2: Pulmonary arteriovenous malformations are a risk factor for bacterial brain abscess; some have a history of recurrent nosebleeds, with visible mucocutaneous telangiectasias on exam. Suggests all brain abscess pts should be screened for PAVM. https://t.co/KAtOECbJOn
— Paul Sax (@PaulSaxMD) February 20, 2020
3. Chronic meningitis — must be one of the most difficult diagnoses in all of ID.
Day #3: Chronic meningitis is CSF pleocytosis that persists for at least 4 wks without spontaneous resolution. ID, autoimmune, and neoplastic processes may be causative; up to 30% no Dx. Next gen sequencing may help. @Yijia_89 @rose_m_olson https://t.co/ZAbUMFOljW
— Paul Sax (@PaulSaxMD) February 21, 2020
4. A convenient cefazolin dosing strategy in hemodialysis — thanks to Dr. Chris Bland, who pointed out this even better study. A real game-changer for inpatient ID consult services everywhere.
Day #4: Cefazolin dosed post-hemodialysis is an ideal strategy for treating MSSA infections in patients with ESRD, obviating the need for a PICC line or other catheter. Excellent PK; good outcome in this small clinical study of bacteremia. https://t.co/nfRca4S49t
— Paul Sax (@PaulSaxMD) February 22, 2020
5. With cutaneous lesions that may be zoster, PCR is the diagnostic test of choice — much better than both culture (which lacks sensitivity) and direct fluorescent antibody (DFA) testing, which is highly dependent on getting enough cells.
Day #5: PCR is the diagnostic test of choice for cutaneous VZV, greatly surpassing viral culture in sensitivity (and also much less operator dependent than DFA). Of course in many cases, clinical diagnosis is sufficient! https://t.co/pt3z80fecA
— Paul Sax (@PaulSaxMD) February 23, 2020
6. You know those patients with a positive syphilis screening test, a positive confirmatory test, but a negative RPR? Well, as we’ve discussed before, they’re quite unlikely to have neurosyphilis.
Day #6: In a study of 265 CSF exams, not a single case of neurosyphilis was diagnosed among those whose blood VDRL was negative. Similar study from Hopkins with RPR. h/t Khalil Ghanem https://t.co/lkyu3sNiKL pic.twitter.com/ptk0ScztFy
— Paul Sax (@PaulSaxMD) February 24, 2020
7. When scanning your HIV patient’s historical genotypes, if you find Y188L, that eliminates the entire NNRTI class of drugs. It’s also naturally present in all HIV-2 isolates.
Day #7: Universal resistance of HIV-2 to NNRTIs is due to the Y188L polymorphism, which appears in all HIV-2 isolates. (Similarly, when seen in HIV-1, Y188L confers resistance to all NNRTIs, including doravirine, +/- etravirine.) @Yijia_89 https://t.co/tpeGG1Upgn
— Paul Sax (@PaulSaxMD) February 25, 2020
It is very good information, thank You
Thank you Dr Paul for sharing those vital “pearls” in ID…I think that Corona would run its course and over a period of time ,with more accessibility to testing would prove to have a far less mortality rate compared to what’s projected now.
Dr John Paul here