Daily Archives: May 1, 2020

Lecture Notes from April 8th

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Notes from our conference on April 8th. If you have any corrections or comments please feel free to add!

Oncologic Emergencies

Neutropenic Fever

Definition: Fever (>101 F or >100.4 F for an hour) with ANC<500, typically avoid rectal temperatures (although no actual evidence of induced bacteremia)

Cause: Often caused by chemotherapy, WBC declines to nadir and then comes back up

  • Also myelodysplastic syndromes, post viral, medication side effect

Clinical Presentation: Often no typical signs of infection (due to lack of response)

Management: Cultures (including from any central access, sometimes fungal), +/-CSF studies, viral testing, typical infectious work-up

  • Reverse isolation, broad spectrum abx, otherwise typical therapy
  • Low threshold for hydrocortisone
  • Neutropenic enterocolitis: Typically presents with RLQ pain with neutropenia
  • Some clinical decision tools, varied validation, look up if interested

Hypercalcemia of Malignancy

General: up to 30%, most common with lung and breast cancers

Pathophysiology: Decreased GI motility, decreased muscular contractions

Mechanisms: PTH-related protein production, Vitamin D analog production, increased osteoclast activity

Treatment: Fluids, bisphosphonates, calcitonin, glucocorticoids, dialysis (for severe cases)

Tumor Lysis Syndrome

General: Typically after initiation of chemotherapy or during times of high cell turnover, found with hematologic malignancies

Clinical Presentation: Electrolyte abnormalities (hypocalcemia, hyperphosphatemia, hyperkalemia), elevated uric acid, acute renal injury, cardiac dysrhythmias, seizures

Treatment: Fluids, rasburicase, correct electrolyte abnormalities and treat as appropriate, dialysis for severe cases

-Correct calcium only if symptomatic to avoid crystallization with high phosphate load

Urinary Diversions

Types:

  • Ileal conduit: incontinent, portion of the bowel with ureters attached to one side and the other attached to skin, drains into urostomy bag
  • Indiana pouch: Similar to above with ileocecal valve making up the collecting pouch, ureters attached to onse side and the distal cecum attached to the skin, ileocecal valve functions as sphincter, urine drained by self-cath
  • Neobladder: Segment of bowel resected and made into a bladder-like sac, one side attached to ureters and the other attached to urethra, varying degrees of incontinence depending on preservation of nerves and sphincter tone, possible to urinate volitionally 

General: Since all of these diversions are made from bowel they are colonized with bacteria and will always have +UA, best practice is cleaning of skin site and catheter specimen sent for culture, diagnosis can also be made by stranding on CT

Clinical Presentation: More often nausea, vomiting, flank pain (different innervation than typical urinary system so will more closely approximate visceral/enteric nociceptor patterns)

Hypersensitivity Reactions

Types:

  • Type 1: Immediate, mediated by IgE (causes histamine release from mast cells)
    • Examples: classic allergic response, anaphylaxis
  • Type 2: Antibody mediated (autoimmune disease mediated by autoantibody against a self target)
    • Examples: Graves disease, Myasthenia, Autoimmune hemolytic anemia, Goodpasture’s 
  • Type 3: Immune complex mediated (autoimmune disease due to deposition of antibody/antigen complexes)
    • Examples: glomerulonephritis, SLE, RA, HSP
  • Type 4: T cell mediated
    • Examples: Tuberculin skin test, contact dermatitis, DM1, RA, IBD, MS

General: Should always be on the differential, often mimic infectious or traumatic pathologies. If you don’t think of them you won’t diagnose them