A Life-saving diagnosis, just by luck!

Sometimes, It is Better to be Lucky than Smart!

Reason for the consult: ED called for severe headache for almost a month, "She looks like having really bad headache", ED physician explained.

Story: A 47-year-old right-handed female with known metastatic breast cancer on Keytruda, anxiety, marijuana and meth use , who presented with severe headache.

Patient reports she slipped in Walmart in 02/24 and has been left shoulder pain and occipital headache since. Headache persisted so she went to see a chiropractor 2 weeks ago. After the first visit, headache had worsened from mild-moderate to severe holocranial pulsating headache with pulsating sound in the ears. After the second visit, headache was more in left side and severe. Headache persisted over the past 2 weeks with nausea/vomiting over the past few days. Along with the headache she has photophobia and bright spots in her vision. She denies prior migraines, she reports using marijuana daily. She reports intermittent use of meth, however last time she used it after headache started not before.

Exam: Normal non-focal exam, no neck pain, facial expression of severe pain.

Workup in ED:

  • CBC: mild leukocytosis 14.3k mainly neutrophils 89%
  • BMP: mild hyponatremia 128
  • Non-contrast CT-head: unremarkable
  • Can't get MRI due to metal implants

What is your differential diagnosis so far?? 

Patient has multiple risk factors for different types of severe headaches:

  • Occipital headache started after a fall -> can be vertebral dissection
  • Headache got worse after chiropracter visit -> another reason to consider dissection
  • Uses marijuana and sometimes meth -> marijuana and meth can cause RCVS
  • Metastatic breast cancer -> brain mets, however CT head without contrast didn't show any vasogenic edema
  • Keytruda -> can cause aseptic meningitis
  • Headache with positive visual symptoms and sensory phobia -> can be migraine

What is your next step?? 

  • Started on magnesium and hydroxyzine for headache till workup is done
  • I ordered CTA head and neck to screen for dissection or RCVS -> CTA was unremarkable
  • Unfortunately can't get MRI
  • CSF was ordered for having leukocytosis along with the headache, also Keytruda can cause aseptic meningitis.
    • CSF results: WBCs 33, RBCs 0, protein 23, glucose 37
    • Meningitis PCR panel was negative
    • WBC differential showed 10% lymphocytes and 90% "other cells".
    • Cytology revealed other cells are malignant adenocarcinoma cells.

Diagnosis: Carcinomatous meningitis

Oncology team was called, plan for Omaya catheter and intrathecal chemotherapy

Take home point: 

  • Don't stick to the common diagnosis and ignore other rare diseases. Patient could be treated as migraine after CTA was negative and discharged home.
  • Although CSF was ordered for another reason (to rule out viral infection due to leukocytosis or Keytruda aseptic meningitis), it did show a more serious diagnosis. Better be lucky than smart!