65 yo M with a lung transplant and hypoxia

OBJECTIVES:

  • Have a framework of how to approach hypoxia in a lung transplant patient

CASE:

65 yo M with a history of BOLT  for COPD ~10 years ago presents with four days of subjective fevers, dyspnea and nonproductive cough. He denies any URI symptoms (sore throat, congestion, rhinorrhea), chest pain, orthopnea, LE swelling. He denies any recent sick contacts.

He has a complicated PMH (full medical history and medication list) notable for CMV D+/R- BOLT ~ 10 years ago that was complicated by acute cellular rejection 3 weeks prior to presentation. He was hospitalized and treated with rabbit-derived ATG (r-ATG) and 3 days of high dose steroids. He is on tacrolimus and prednisone for immunosuppresion; Bactrim and valganciclovir for prophylaxis.

On exam, he was febrile to 38.9C, HR 131, RR 22, SBP 100-140s/90s, SaO2 93% on 2LNC. He is in no respiratory distress and has crackles at the bases only. He has dry mucus membranes, normal JVP and no LE edema. His initial labs were notable for a BUN 23, Cr of 1.3 (from baseline of 0.9), WBC 24 with 95% neutrophils (full labs). EKG showed sinus tachycardia without ischemic changes.

CXR on admission and on HD1 (after 2L IVF) showed:


What is your differential diagnosis for hypoxia in this patient? 

What additional work-up would you want?


CASE CONTINUED: 

FINAL DIAGNOSIS:

His BAL cultures were ultimately negative. What is the yield of a bronchoscopy for diagnosing pneumonia in an immunosuppressed patient? How is this affected by the initiation of antibiotics? (~ 2-3 min)


TAKE HOME POINTS: 


ADDITIONAL LEARNING (~10-15 min):


REFERENCES:

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