Sodium Deficiency (Hyponatremia): Or something else? Differential Diagnosis

Endocrine, nutritional, and metabolic diseases (E00-E90).

  • Hypercorticism (Cushing’s disease: hypercortisolism; excess of cortisol).
  • Hypothyroidism (hypothyroidism).
  • Addison’s disease (primary adrenocortical insufficiency) – 84% of patients had serum sodium <137 mmol/l at the time of diagnosis
  • Adrenocortical insufficiency (NNR insufficiency; adrenocortical insufficiency).
  • Syndrome of inadequate ADH secretion (SIADH) (synonym: Schwartz-Bartter syndrome) – there is an inappropriately high secretion of antidiuretic hormone (ADH; ADH excess) in relation to blood plasma osmolality; this leads to too little fluid excretion via the kidneys with the formation of a highly concentrated urine; the result is hyperhydration (overhydration) with dilutional hyponatremia (“dilutional sodium deficiency”), which can lead to cerebral edema (brain swelling). Etiology (causes): paraneoplastic in approximately 80% of cases in patients with small cell lung cancer; other possible causes include: Cerebral hemorrhage, brain tumor, meningitis (meningitis, encephalitis (brain inflammation), Legionella pneumonia (pneumonia caused by the pathogen Legionella pneumophilia), tuberculosis, carcinoma (diagnosis of exclusion)Symptoms: Nausea (nausea), anorexia (loss of appetite), cephalgia (headache).

Cardiovascular system (I00-I99).

  • Heart failure (cardiac insufficiency)
  • Hypotension (low blood pressure)

Infectious and parasitic diseases (A00-B99).

  • Diarrhea (diarrhea)

Liver, gallbladder, and biliary tract-pancreas (pancreas) (K70-K77; K80-K87).

  • Liver cirrhosis (irreversible damage to the liver associated with marked remodeling of liver tissue) with ascites (abdominal dropsy).
  • Pancreatitis (inflammation of the pancreas).

Mouth, esophagus (esophagus), stomach, and intestines (K00-K67; K90-K93).

  • Ileus (intestinal obstruction)
  • Peritonitis (inflammation of the peritoneum)

Psyche – nervous system (F00-F99; G00-G99)

Symptoms and abnormal clinical and laboratory findings not elsewhere classified (R00-R99).

  • Vomiting
  • Diarrhea (diarrhea)
  • Polydipsia (excessive thirst)

Genitourinary system (kidneys, urinary tract – reproductive organs) (N00-N99)

  • Chronic renal failure (slowly progressive reduction in renal function).
  • Nephrotic syndrome – collective term for symptoms that occur in various diseases of the glomerulus (renal corpuscles); the symptoms are proteinuria (increased excretion of protein in the urine) with a loss of protein; hypoproteinemia, peripheral edema (water retention) due to hypoalbuminemia (decreased level of albumin in the blood), hyperlipoproteinemia (lipid metabolism disorder).
  • Salt loss kidney

Injuries, poisonings and other consequences of external causes (S00-T98).

  • Muscle trauma
  • Burns

Medication

  • See “Causes” under medications

Operations

  • Transurethral resection of the prostate (TURP; removal of the prostate through the urethra).

Other differential diagnoses