Symptom Finder - Nocturia
NOCTURIA
The differential diagnosis of nocturia is similar to that of polyuria. A pathophysiologic analysis of the symptoms would indicate that the patient is producing excessive urine at night, there is an obstruction to the output of urine so that the bladder cannot be emptied fully on one voiding, or there is an irritative focus in the urinary tract stimulating the patient to urinate more frequently.
1. Excessive urine production at night: This category includes all the causes of polyuria: diabetes insipidus, diabetes mellitus, hyperthyroidism, diuretic drugs, nephrogenic diabetes insipidus, and chronic nephritis. In addition, the one condition that produces excessive urine output almost exclusively at night—congestive heart failure—must be considered. In heart failure, edema accumulates in the extremities during the day while the patient is in the upright position and is returned to the circulation and poured out through the kidneys at night while the patient is in the recumbent position.
2. Obstructive uropathy: Bladder neck obstruction by a calculus, enlarged or inflamed prostate, median bar hypertrophy, or urethral stricture is a condition to consider here. Neurogenic bladder from poliomyelitis, multiple sclerosis, and other spinal cord diseases
must also be considered.
3. Irritative focus in the urinary tract: Nocturia may result from inflammation of the bladder, prostate, urethra, and kidney on this basis. Occasionally a bladder tumor or prostate carcinoma may be the irritative focus. Inflammation of the vagina, fallopian tubes, and rectum are also occasionally responsible.
Approach to the Diagnosis
The workup of nocturia is essentially the same as the workup of polyuria and urinary frequency.Obviously, the search for obstruction and infection are most important. Venous pressure, circulation time, and pulmonary function studies to rule out congestive heart failure should be done if the urinary tract is clean.
The differential diagnosis of nocturia is similar to that of polyuria. A pathophysiologic analysis of the symptoms would indicate that the patient is producing excessive urine at night, there is an obstruction to the output of urine so that the bladder cannot be emptied fully on one voiding, or there is an irritative focus in the urinary tract stimulating the patient to urinate more frequently.
1. Excessive urine production at night: This category includes all the causes of polyuria: diabetes insipidus, diabetes mellitus, hyperthyroidism, diuretic drugs, nephrogenic diabetes insipidus, and chronic nephritis. In addition, the one condition that produces excessive urine output almost exclusively at night—congestive heart failure—must be considered. In heart failure, edema accumulates in the extremities during the day while the patient is in the upright position and is returned to the circulation and poured out through the kidneys at night while the patient is in the recumbent position.
2. Obstructive uropathy: Bladder neck obstruction by a calculus, enlarged or inflamed prostate, median bar hypertrophy, or urethral stricture is a condition to consider here. Neurogenic bladder from poliomyelitis, multiple sclerosis, and other spinal cord diseases
must also be considered.
3. Irritative focus in the urinary tract: Nocturia may result from inflammation of the bladder, prostate, urethra, and kidney on this basis. Occasionally a bladder tumor or prostate carcinoma may be the irritative focus. Inflammation of the vagina, fallopian tubes, and rectum are also occasionally responsible.
Approach to the Diagnosis
The workup of nocturia is essentially the same as the workup of polyuria and urinary frequency.Obviously, the search for obstruction and infection are most important. Venous pressure, circulation time, and pulmonary function studies to rule out congestive heart failure should be done if the urinary tract is clean.
