Narges presented a case of a middle age woman without any prior medical history, presenting with 1 week of bruising, epistaxis, and bleeding from her gums. Her initial lab work was notable for a WBC of 52.2 with 92% blasts, later confirmed to be AML. She developed a fever and a rash over the next few days… She had neutropenic fever, and around the same, time, developed AML-associated Sweet’s Syndrome!

AML: A quick overview

Accounts for 80% of acute leukemias in adults

Risk Factors

• Benzene exposure
• Radiation exposure, commonly 7-10 years after exposure
• Prior tx with alkylating agents and topoisomerase II inhibitors like doxorubicin, etoposide.
• Age: greatest risk factor, older = at high risk, median age 65
• CML, MDS, and myeloproliferative syndromes have a chance to evolve into AML.

Initial presentation

• Bruising, gum bleeding, epistaxis from thrombocytopenia
• SOB, DOE, fatigue from anemia
• Pyogenic infections of the skin
• HSM found in 1/3 of pts
• 50% might have gingival hyperplasia as first signs of the disease
• Small subset might have concurrent HLH on presentation
• If fever, almost always infection

Diagnosis

• Buzz words: blasts on smears, Auer rods (peroxidase stain)
• > 20% blasts cells
• Flow cytometry
  • CD117, CD33 most common
  • CD19, if seen, suggests lymphoblastic origins
• Subtypes
  • M3 (Acute promyelocytic leukemia), t(15; 17), prone to DIC, responsive to ATRA and potentially can be cured.
    • If pt receiving ATRA +/- Arsenic trioxide develop pulmonary sx think of an entity called Differentiation Syndrome, can be life threatening, stop treatment and give steroids.
  • Non APL: Everything else

Management:

• Induction, consolidation (after complete remission, assess induction response via BM bx) via HiDAC high dose cytarabine, or autologous CT, or allogeneic HCT, maintenance (usually not needed but can be beneficial in some types of AML)
• APL: ATRA +/- ATO
• Non-APL: 7 day course of cytarabine and 3 day course of an anthracycline. For older pts with more comorbidities, can use a milder regimen with azacytidine or decitabine.

 

Neutropenic fever

Definition: T > 38.3 or > 38 sustained over 1 hour, with neutropenia (ANC < 500)

Determine high risk or low risk

• Low Risk: Anticipated neutropenia < 7 days, clinically stable, NO medical comorbidities
  • IDSA: Can consider outpatient antibiotics, Cipro + Augmentin and able to tolerate PO, otherwise inpatient management
• High Risk: Anticipated neutropenia > 7 days, clinically unstable, any medical comorbidities
  • Automatically inpatient management
  • Monotherapy with pseudomonal coverage initially is recommended by IDSA
    • Cefepime: 2g Q8H, higher dose than usual
    • Meropenem 1g Q8H
    • Imipenem
    • Zosyn 4.5g Q6-8
    • Ceftazidime increasingly avoided.
  • If history of MRSA, e/o catheter infection, skin infection, pneumonia, or unstable, add Vancomycin/MRSA coverage
  • PCN allergy: Can consider using Aztreonam, cipro
  • If recurrent of persistent fever after 4-7 days: Add an empiric antifungal, most of the time cover for candida since it’s the most common cause of invasive fungal infection.
    • Echinocandin is favored i.e. caspofungin, increasing azole resistance in candida.
    • Think aspergillus if e/o pulmonary nodules, ampho B and voriconazole then are preferred

Sweet’s Syndrome

Uncommon, inflammatory disorder, usually affects pts ages 30-60. Older = more likely malignancy associated

Presentation:

• Abrupt, painful, edematous (juicy), erythematous papules/plaques/nodules + fever and leukocytosis.
• Rare mucosal/oral involvement.
• Can also rarely causes inflammation of a particular organ system, i.e eye, liver, heart, CNS, kidney, even bone.

Image adapted from Derm 101

Types

• Classic
  • Idiopathic, majority of cases
  • Associations: Infections (URI, GI) 1-3 weeks after infection
  • IBD
  • Pregnancy
  • HIV, TB, hepatitis, autoimmune conditions
  • Possible inc risk of malignancy
• Malignancy associated
  • AML is the malignancy most associated with Sweet’s Syndrome.
  • Risk:
• Drug-induced (long list but some of the potential ones we used more commonly are):
  • Bactrim, Macrobid, AED, hydralazine, clozapine, PTU, GCSF, Mirena, Lasix, Azathioprine, ATRA

Dx Criteria: both majors and 2 minors are required

• Majors
  • Abrupt onset of painful erythematous plaques or nodules
  • Histopath evidence of dense neutrophilic infiltrate without evidence of leukocytoclastic vasculitis
• Minor:
  • > 38C
  • Underlying malignancy, IBD, pregnancy, or recent upper resp, GI infection, or vaccination
  • Steroid responsive
  • Labs: ESR > 20, CRP elevated, leukocytosis > 8000 with > 70% neutrophils)

Biopsy: Dense, neutrophilic infiltrate in the dermis, w/o e/o vasculitis.