Symptom Finder - Excessive Sweating
EXCESSIVE SWEATING
It is uncommon for patients to present with the chief complaint of excessive sweating (diaphoresis, hyperhidrosis); when they do, it is often hyperhidrosis of the hands and feet due to caffeine or nervous tension.
Obese patients may complain of excessive sweating, especially under the armpits. What are the pathologic causes of sweating and how can they be recalled?
Physiology is the basic science most useful in developing a differential diagnosis. The sweat glands are under the control of the sympathetic nervous system; consequently, they respond to anything that increases the level of adrenalin in the body. Shock from any cause induces a reflex stimulation of the sympathetic nervous system and adrenal gland and an outpouring of adrenalin. Thus diaphoresis may be found in myocardial
infarctions and CHF (cardiogenic shock); in pulmonary embolism, renal embolism, and peripheral embolism (vasomotor shock); and in bleeding peptic ulcer, pyloric obstruction with vomiting, cholera, intestinal obstruction, and other forms of shock due to a drop in blood volume.
Acute labyrinthitis or seasickness causes sweating by neurogenic shock pathways.
The adrenalin level may also be increased in the body in hypoglycemic states. Thus, a patient with diabetes in insulin shock will sweat, whereas a patient with diabetes in acidosis will not. Islet cell adenomas cause diaphoresis during the hypoglycemic attacks. Hepatic hypoglycemia, glycogen storage disease, and hypopituitarism may all be associated with excessive sweating on the same basis. Excessive adrenalin output is the cause of diaphoresis in pheochromocytomas. It may be the cause in hyperthyroidism also, although another mechanism discussed below is undoubtedly involved.
Hypermetabolism causes excessive sweating by hypothalamic stimulation of the sweating center to assist in the cooling of the body. Thus, any cause of fever is associated with sweating (the sweating induces a drop in temperature). Most notable of these causes are rheumatic fever, pulmonary tuberculosis, and septicemia. An abscess large enough to cause fever will probably cause sweating. Hypermetabolism in hyperthyroidism is largely responsible for the continuous sweating, although excessive adrenalin is involved too. Neoplasms, especially leukemia and metastatic carcinoma, are associated with sweating on the same basis.
A miscellaneous group of conditions associated with diaphoresis that are also due to physiologic mechanisms include neurocirculatory asthenia, chronic anxiety neurosis, menopause; and various drugs, including camphor, morphine, and ipecac. Organophosphate intoxication may produce excessive sweating by allowing excessive accumulation of acetylcholine at the synaptic junction.
Approach to the Diagnosis
Pinpointing the diagnosis involves a search for other symptoms and signs of the above conditions. A chest x-ray film to rule out pulmonary tuberculosis is especially important in a patient presenting with night sweats. Accurate charting of the temperature will indicate those cases due to fever. Urine vanillylmandelic acid (VMA) levels and a thyroid profile will spot pheochromocytomas and hyperthyroidism. A 36- to 48-hour fast with frequent glucose determinations will help diagnose insulinomas and other hypoglycemic states. Because this is not usually the major presenting symptom, the workup will usually center on another symptom. Asking about caffeine ingestion will often spot the cause without expensive laboratory testing.
Other Useful Tests
1. CBC (anemia, infection)
2. Sedimentation rate (infection)
3. Rheumatoid arthritis test
4. Serum insulin assay (insulinomas)
5. C-peptide (insulinomas)
6. Urine cultures (pyelonephritis)
7. Blood culture (subacute bacterial endocarditis [SBE])
8. Chemistry panel (liver disease, kidney disease)
9. Drug screen (drug abuse)
10. Psychometric testing (chronic anxiety neurosis)
It is uncommon for patients to present with the chief complaint of excessive sweating (diaphoresis, hyperhidrosis); when they do, it is often hyperhidrosis of the hands and feet due to caffeine or nervous tension.
Obese patients may complain of excessive sweating, especially under the armpits. What are the pathologic causes of sweating and how can they be recalled?
Physiology is the basic science most useful in developing a differential diagnosis. The sweat glands are under the control of the sympathetic nervous system; consequently, they respond to anything that increases the level of adrenalin in the body. Shock from any cause induces a reflex stimulation of the sympathetic nervous system and adrenal gland and an outpouring of adrenalin. Thus diaphoresis may be found in myocardial
infarctions and CHF (cardiogenic shock); in pulmonary embolism, renal embolism, and peripheral embolism (vasomotor shock); and in bleeding peptic ulcer, pyloric obstruction with vomiting, cholera, intestinal obstruction, and other forms of shock due to a drop in blood volume.
Acute labyrinthitis or seasickness causes sweating by neurogenic shock pathways.
The adrenalin level may also be increased in the body in hypoglycemic states. Thus, a patient with diabetes in insulin shock will sweat, whereas a patient with diabetes in acidosis will not. Islet cell adenomas cause diaphoresis during the hypoglycemic attacks. Hepatic hypoglycemia, glycogen storage disease, and hypopituitarism may all be associated with excessive sweating on the same basis. Excessive adrenalin output is the cause of diaphoresis in pheochromocytomas. It may be the cause in hyperthyroidism also, although another mechanism discussed below is undoubtedly involved.
Hypermetabolism causes excessive sweating by hypothalamic stimulation of the sweating center to assist in the cooling of the body. Thus, any cause of fever is associated with sweating (the sweating induces a drop in temperature). Most notable of these causes are rheumatic fever, pulmonary tuberculosis, and septicemia. An abscess large enough to cause fever will probably cause sweating. Hypermetabolism in hyperthyroidism is largely responsible for the continuous sweating, although excessive adrenalin is involved too. Neoplasms, especially leukemia and metastatic carcinoma, are associated with sweating on the same basis.
A miscellaneous group of conditions associated with diaphoresis that are also due to physiologic mechanisms include neurocirculatory asthenia, chronic anxiety neurosis, menopause; and various drugs, including camphor, morphine, and ipecac. Organophosphate intoxication may produce excessive sweating by allowing excessive accumulation of acetylcholine at the synaptic junction.
Approach to the Diagnosis
Pinpointing the diagnosis involves a search for other symptoms and signs of the above conditions. A chest x-ray film to rule out pulmonary tuberculosis is especially important in a patient presenting with night sweats. Accurate charting of the temperature will indicate those cases due to fever. Urine vanillylmandelic acid (VMA) levels and a thyroid profile will spot pheochromocytomas and hyperthyroidism. A 36- to 48-hour fast with frequent glucose determinations will help diagnose insulinomas and other hypoglycemic states. Because this is not usually the major presenting symptom, the workup will usually center on another symptom. Asking about caffeine ingestion will often spot the cause without expensive laboratory testing.
Other Useful Tests
1. CBC (anemia, infection)
2. Sedimentation rate (infection)
3. Rheumatoid arthritis test
4. Serum insulin assay (insulinomas)
5. C-peptide (insulinomas)
6. Urine cultures (pyelonephritis)
7. Blood culture (subacute bacterial endocarditis [SBE])
8. Chemistry panel (liver disease, kidney disease)
9. Drug screen (drug abuse)
10. Psychometric testing (chronic anxiety neurosis)
