446) A 64 year old woman presents to your office with productive cough and fever for the past three days. About two months ago, she was admitted for pneumonia. Past medical history is significant for Rheumatoid arthritis. Her medications include hydroxychloroquine and prednisone. Previously, she was treated with Azathiprine for about 6 years.
On examination, temperature is 101F, blood pressure 120/80 and heart rate of 106/min. Chest examination reveals decreased breath sounds at left lower lobe. No hepatomegaly, spleen tip is palpable. Chest X-Ray reveals left lower lobe consolidation Labs reveal WBC 1000/µl with differential count showing neutrophils of 30% and Hemoglobin 9.9 gm%
Which of the following is the most likely explanation for the patient’s presentation?
A) Hypogammaglobulinemia from Rheumatoid arthritis
B) Marrow suppression by Hydroxychloroquine
C) Marrow toxicity by Azathiprine
D) Myeloproliferative disorder
E) Felty Syndrome
Filed under: Uncategorized, USMLE Test Prep | Tagged: archer general internal medicine, Archer hematology, Archer Rheumatology, Hematology, usmle hematalogy, USMLE step 3 Hematology, USMLE step 3 Rheumatology |
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felty’s syndrome – Felty’s syndrome, also called Felty syndrome is characterized by the combination of rheumatoid arthritis, splenomegaly and neutropenia. People with this syndrome are at risk of infection because they have a low white blood cell count.
C. Looks like she has a myelo dysfunction d/t Azathioprine causing hypogamaglobulinemia and susceptibility to infectious dz.
Thinking about Felty’s, but can be a presentation of drug toxicity too. So the whole issue zeroes down to how to differentiate between the 2 things.
E
c
So, let’s think what is more likely: Is that this specific patient, whom by the way is taking two extremely toxic drugs has a side effect from one of these drugs OR that this patient has a syndrome not so common called Felty’s Syndrome. I still stick to my side effect. In real life I would think of it before jumping into a diagnosis of Felty.
C
The answer is Felty syndrome. The fact that she has chronic rheumatoid arthritis + Neutropenia + splenomegaly are sufficient to make this CLINICAL Dx. This neutropenia could not defend this pt. from opportunistic infections that is why she ended up with left lower lobe pneumonia. Now, don’t get me wrong, you still have to r/o the other 4 DDX (in the real world), but for the sake of taking a test, the answer is “Felty syndrome”.
My only ” difficulty ” to reconcile with the Dx of Felty is that the question asks for ” the most likely ” explanation for this presentation. Now my question: How frequent or common Felty Syndrome is? I never saw one.
I am thinking of Felty’s most probably based on the fact that there is no hepatomegaly in this patient. In fact hepatomegaly is a possibility in either of the cases, but more common with drug induced toxicity. That is the only thing I can consider at this point. any other thoughts are appreciated.
E
Felty can explain splenomegaly.
Marrow suppression should suppress Erythroblast series which looks normal and no splenomegaly.
E:)
E 🙂
the most likely explanation would be marrow toxicity secondary to cytotoxic drugs azathiaprine and hydroxychloroquine, but he was on azathiaprine for 6 yrs and only recently started the hydro., myelosupression and anaemia are expected changes and there will be splenomegaly surely due to compensatory measures ..missing something here?? Felty syndrome i think is a distractor because of the rheumatoid arthritis in the history, but emphasis is surely on the side effects of long term treatment of RA with azathiaprine which causes increased infections due to neutropenia and hypogammaglobulinaemia