Hypercalcemia

Today we discussed hypercalcemia. Some issues that came up:


Vomiting

One of many possible approaches:

Intraperitoneal causes

Obstruction: pylorus (gastric outlet obstruction), SBO, LBO
Infection: viral gastroenteritis, bacterial
Inflammation: cholecystitis, pancreatitis, appendicitis, hepatitis
Motor: gastroparesis, GERD, esophageal spasm

Extraperitoneal causes

Cardiovascular: MI, CHF
CNS: cerebellar, brainstem, raised ICP (masses, bleed, hydrocephalus), migraine
Inner ear: labyrinthitis
Medications: post-op, chemotherapy, antibiotics, OCP, oral hypoglycemics
Metabolic: uremia, hepatic failure, calcium, sodium, DKA, adrenal insufficiency
Pregnancy

Clues:
Bilious suggests from distal to duodenum
Undigested food suggests gastric outlet obstruction, gastroparesis or Zenker's diverticulum
Feculent suggests colonic obstruction
Immediately after eating suggests gastritis, gastric outlet obstruction


Hypercalcemia

Symptoms: GI- anorexia, n/v, abdo pain, constipation. Renal: stones, polyuria. Neuro: weakness. Cardiac: arrhythmias

Etiology:
Useful first division is by PTH level

1) High PTH- expect high Ca, low PO4.
A) primary/secondary/teriary hyperparathydoidism, parathyroid hyperplasia
B) lithium
C) familial hypercalcemic hypocalciuria

2) Low PTH
PTHrP from malignancy (esp. SCC- lung, H+N)
hypervitaminosis D- expect high Ca and high PO4- from granulomatous disease, lymphoma)
OAF = IL6 (local paracrine effect; in breast and hematological cancers)
Direct effect of mets (e.g. prostate, lung, etc.)
Myeloma
Medications- HCTZ, Ca, vit. D
Milk alkali syndrome
Hyperthyroidism

As inpatient, #1 cause = malignancy
As outpatient, #1 cause = primary hyperpara


Tx: Fluids!. Consider bisphosphonate if malignancy-related or v. high (but takes days to work)
Calcitonin by nasal spray or subq. If hyper D from sarcoid or lymphoma, possible steroids. Avoid lasix since most patients are profoundly volume depleted. Last resort is dialysis


Milk-Alkali syndrome

Triad of hypercalcemia, met alk, renal failure assoc with ingestion of large amts calcium, alkali

Once common because of PUD treatement. Making resurgence b/c of calcium for osteoporosis, and prevention of secondary hyperparathyroidism in CKD

Sequence: hypercalcemia, dec GFR, met alkalosis ("contraction"). Hypercalcemia per se stimulates renal bicarb fomation.

Pts on vit D, thiazides, vol contraction, CKD are at higher risk


Some links:

Click here for NEJM clinical problem solving case on hypercalcemia

Click here for a review of calcium disorders in renal disease