Primary polydipsia—compulsive water drinking

December, 1968 T h e Journal o[ P E D I A T R I C S

845

Primary polydipsia-compulsive water drinking Report oJ two cases Two children with primary polydipsia (compulsive water drinking) are reported. Each child had an organic central nervous system disease known to cause diabetes ~nsipidus. However, each child concentrated urine normally and had a normal blood level of antidiuretic hormone. A background o/ common e~otionality, similar to that observed in the compulsive eater, was noted clinically in both children and was substantiated by psychologic examination, thus suggesting the diagnosis of psychogenic polydipsla. However, as lesions o[ the central nervous system are known to effect the sensation of thirst, the primary polydipsia exhibited by both children could be attributed equally well to organic hypothalamie disease. The precise cause of the polydipsia exhibited by these children must, there[ore, remain in doubt.

R i c h a r d M. Stevko, M.D., Maridee BaMey, M.D., and William E. Segar, M.D. "x" INDIANAPOLIS,

IND.

T H E O N S E T of excessive thirst accomp a n i e d by the production of copious amounts of urine is usually a consequence of a disease process t h a t produces polyuria, such as diabetes insipidus. T h e polydipsia is essential and represents an effort to m a i n t a i n homeostasis. As it is a consequence of a b n o r m a l water loss, it can be t e r m e d "secondary." P r i m a r y polydipsia, however, can be defined as the ingestion of water in excess of that required to m a i n t a i n n o r m a l w a t e r balance. From the" Department o/ Pediatrics, Indiana University School of Medicine. This investigation was supported in part by Research Grant No. HE-10401 /rom the National Institutes of Health, Public Health Service, and by the ]ames Whitcomb Riley Memorial Association. "X'Present address: Section of Pediatrics, Mayo Clinic and Mayo Foundation, Rochester, Minn. 55901.

This r e p o r t describes 2 children who h a d diseases which ordinarily cause diabetes insipidus a n d who, indeed, m a y h a v e h a d true diabetes insipidus at the onset of their illnesses. However, it was p r o v e d t h a t each child h a d p r i m a r y polydipsia r a t h e r than diabetes insipidus.

CASE REPORTS Case 1. A 10-year-old Caucasian boy was hospitalized when he was 3 years of age because of a 4 week history of extreme thirst, polyuria, and loss of 5 to 10 pounds. He had not talked until he was 2 years of age, but his development had been otherwise normal. The results of physical examination were normal. The specific gravity of the urine was 1.000. A normal sella turcica and multiple, large, well-defined osteolytic lesions of both parietal bones were seen on roentgenographic examination of the skull. Biopsy VoI. 73, No. 6, pp. 845-851

846

Stevko, Balsley, and Segar

revealed typical morphologic changes of histiocytosis X. The skeletal lesions were irradiated, and vasopressin (Pitressin) was given by insufltation for control of the diabetes insipidus. The patient was first seen at the Indiana University Medical Center in October, 1963, when he was 6 ~ years of age, because of diabetes insipidus and for evaluation of growth failure. Specific gravity of the urine was 1.003, and it increased to 1.016 after administration of vasopressin. During hospitalization, a nurse noted that he "is a very clinging and very lonesome child." The initial daily urinary volume was several liters per day without treatment, and 1,000 to 2,000 ml. per day after Pitressin tannate in oil was injected intramuscularly. The boy was readmitted to the Indiana University Medical Center in April, 1967, at the age of 10 years, because of nervousness, school failure, and an excessive intake of water. He had received no Pitressin during the previous year. Serum sodium concentrations of 140 and 146 mEq. per liter were obtained. Fluid restrict'on for 8 hours resulted in an increase in the specific gravity of the urine from 1.006 to 1.020 and a rise in urine osmolality from 96 to 555 mOsm. per kilogram. The level of antidiuretic hormone (ADH) in the blood after the 8 hours of dehydration was 2/~U per milliliter, a value within the normal range (normal blood ADH = 1.6 -+ 0.6 /~U per milliliter),a, 2 and the sodium concentration in serum was 140 mEq. per liter. Psychiatric evaluation was requested to determine whether the appearent mental retardation was organic or functional. The psychiatric history disclosed that the parents' marriage was tumultuous; they were often physically aggressive in front of the patient and his siblings. During the psychologic testing, the patient was noted to be shy and withdrawn and his speech was almost unintelligible. He did not appear to listen to the questions. Answers, when given, were simple and concrete. A "draw a person" test resulted in a poorly done primitive figure enclosed by a frame, representing an achievement at approximately the 6-year-old level. The Wechsler Intelligence Scale for Children full-scale quotient was 56, and the testing disclosed many inconsistencies. These inconsistencies, the patient's adequate vocabulary, and the range of concept elicited on a Rorschach test indicated that he was functioning in the dull-normal range. The result of the Goodenough-Harris drawing test was 2 standard deviations below the average for his age and sex, with a standard score of 72. These studies led

The Journal of Pediatrics December 1968

to the conclusion that the patient's apparent retardation was probably functional, and no evidence of organic brain disease could be demonstrated. Many episodes of incontinence, many attempts to get attention, and much craving for bodily contact were noted by the nursing staff. The patient seldom smiled and appeared very anxious. He gave the impression of being delighted with water the way other children are delighted with candy. He seemed satisfied when given a decreased intake of water (1,500 ml. per day) and commented that his discharge from the hospital was a reward for his decreased drinking of water. Psychotherapy was not undertaken. Case 2. A 12-year-old Caucasian boy was first admitted to the Indiana University Medical Center in October, 1963, when he was 81%2 years of age, because of grow~th failure and diminished activity. He had been in a slowlearner group since the first grade. His height and weight were below the third percentile, and equivocal bilateral optic atrophy was noted on physical examination. Enlargement of the sella turcica was observed on roentgenographic examination, and generalized dysrhythmia of grade 2 was demonstrated by electroencephalography. A lumbar puncture, brain scan, and cerebral angiogram were performed, and no abnormalities were found. The level of protein-bound iodine was 4 /~g per 100 ml. and of 17-hydroxycorticoid excretion, 0.7 mg. per 24 hours. A Fishberg concentration test revealed a urine concentration of 1.023 to 1.026. The patient's daily intake of fluid prior to surgery was 500 to 800 ml. On the twenty-fifth hospital day, a eraniotomy was performed and as intrasellar epidermoid cyst was found. After surgery, the specific gravity of the urine varied from 1.003 to 1.010 and increased to 1.022 after a single intramuscular injection of Pitressin. The patient was hospitalized in June, 1964, at 9 ~ years of age, because of vomiting, sleepiness, and headaches of 1 week's duration. Between admissions he had been drinking excessive amounts of water and was enuretic 6 or 7 times each night. Physical examination revealed a lethargic, sluggish child who did not smile. The temporal pallor of the optic disks was again noted. Serum sodium concentrations of 135 and 137 mEq. per liter were obtained. Initially, the specific gravities of the urine were 1.003 and 1.005. Values of 1.017 and 1.024 were obtained after fluid was withheld for 19

Volume 73 Number 6

and 24 hours, respectively. Urine osmolality increased from 68 to 514 mOsm. per liter, and a normal blood ADH level of 1.0 /~U per milliliter was obtained after 19 hours of fluid restriction. No clinical or laboratory evidence of dehydration was noted despite this prolonged period of fluid restriction. The child was believed to be a compulsive water drinker and ,was referred to the Riley Hospital Child Guidance Clinic. Study at that clinic revealed that the home was chaotic, the patient and his sister were mutually aggressive, and the patient's sister was enuretic. The father described the family as being "everybody for himself." The mother was defensive and proud and unusually dependent on her own family, maintaining contact with them halfway across the continent, although the father's family, who lived in the same city, was seldom seen. Multiple achievement tests and other psychologic examinations, including a Rorschach and a personality inventory test, indicated that the boy was a dull-normal child who was functioning within the normal limits. It was also noted that the child was reserved, underactive, negativistic, soft-spoken (although relevant and coherent), and undisturbed by his enuresis. The findings were consistent with those of a passiveaggressive personality pattern. Subsequent psychotherapy was not successful in altering this child's behavioral difficulties, although voluntary curtailment of his water intake provided some symptomatic relief. COMMENT

Both of these children exhibited polydipsia that could not be attributed to an increased need for water. In the past, such patients have been called "compulsive water drinkers." This term implies that the polydipsia has a psychogenic cause. Because this assumption may not be valid, the term primary polydipsia is preferred. If it can be shown that the polydipsia is caused by a psychogenic or by a neurogenic abnormality, the term psychogenic polydipsia or neurogenic polydipsia would be preferable. Polydipsia is, by definition, fluid ingestion in amounts greater than that normally required to maintain physiologic homeostasis and is almost always found in association with polyuria. Polydipsia arises as a result of a physiologic or psychologic (or both)

Primary poIydipsia

847

drive--thirst--and its understanding is dependent on comprehension of the physiologic basis of thirst. The factors regulating thirst in man are incompletely understood. I t is known, however, that thirst arises from stimulation of various receptors, both locaP and systemic, 4 and is regulated by central, 5 neurohormonal, or endocrine 6, ~ mechanisms, as well as by psychologic factors. Only the roles of the central nervous system and of psychologic factors in the regulation of thirst are germane to the present discussion. Role of the central nervous system. In 1881, Nothnagel 8 described a m a n who became violently thirsty after being kicked in the head by a horse. Nothnagel suggested that a "drinking center" existed in the central nervous system. Bailey and Bremer 9 produced the first experimental evidence for such a center when they demonstrated in 1921 that destructive hypothalamic lesions alter thirst. It is now known that several discrete anatomic regions in the midbrain influence water intake and that these regions respond to stimuli in many ways. Some of these regions are listed in Table I. The lateral hypothalamic region is probably the most important. Ablation of this region severely inhibits thirst and hunger. 5, 10 The hypodipsia produced by a destructive lesion does not result in cessation of prandial or "dry-mouth" drinking b u t does abolish drinking in response to dehydration, hypertonicity, or hyperthermia. Stimulation of that portion of the lateral hypothalamus located between the mammillo-thalamic tracts and the descending columns of the fornix by a weak electric current causes polydipsia to the point of hemodilution and hemolysis. 5 Destructive lesions of the preoptic nucleus or heat-loss center located under the anterior commissure and dorsorostral to the region concerned with A D H production cause adipsia as well as hyperthermla2 ~ H e a t stimulation of this region results in drinking, whereas cooling prevents a dehydrated animal from drinking. Electrical

84 8

Stevko, Balsley, and Segar

The Journal o/ pediatrics December 1968

Table I. Regions of the central nervous system concerned with thirst

Location

Destruction (effect of lesion)

Stimulation Type ] Effect

Lateral hypothalamus

Adipsia5, lo Aphagia a, 10

Electrode Acetylcholine Adrenergic drugs Atropine

Polydipsia~ Polydipsia G Fiyperphagia 7 and adipsia Hypodipsia r

Preoptic nucleus (heat-loss center)

Adipsia 1~ Hyperthermia 1~

Warming Cooling Electrode

Polydipsia ~0 Adipsia 1~ Polydipsiaa 0

Basal tuberaI region

Possible polydipsia ~1

Ventromedial nucleus of hypothalamus

Hypodipsia 12 Hyperphagia 12

Anterior hypothalamus, between fornix and mammillo-thalamic tract, anterior to mammillary region, lateral to paraventral nucleus

Adipsia 5, la

Saline Electrode

Polydipsia a Polydipsia ~

Electrode

Polydipsia1~

Electrode

Polydipsia~

Lateral edge of dorsomedial nucleus behind paraventral nucleus Subcommissural organ

stimulation increases water intake, but to a lesser a m o u n t than that resulting from stimulation of the lateral hypothalamus. Some e v i d e n c e indicates that lesions of the basal tuberal region of the medial hypothalamus, which invariably cause diabetes insipidus, also cause a significant increase in thirst? 1 Lesions in this region m a y account for the disproportionately great thirst exhibited by the occasional patient with diabetes insipidus. Destructive lesions of the ventromedial nucleus of the hypothalamus cause a relative hypodipsia and hyperphagia12; lesions in the anterior hypothalamus located between the fornix and mammillo-thalamic tract and anterior to the mammillary region result in adipsia? ~ Animals with lesions in these 2 regions exhibit prandial and "drym o u t h " drinking but will not drink in response to dehydration or hyperosmolality. Finally, water intake is increased by stimulation of the lateral edge of the dorsomedial nucleus and by stimulation of the subcommissural organ. Destruction of this latter region causes adipsia. 14 Psychologic factors. Drinking, stimulated by factors other than those previously dis-

Adipsia 14

cussed, includes prandial drinking, 1G normal or habit drinking, and psychogenic drinking. PRIMARY

POLYDIPSIA

Primary polydipsia may be due to psychogenic factors, to damage to the central nervous system, or to chronic stimulation of one or more of the extracranial thirst receptors. I n man, fluid consumption is a habit that is conditioned by psychologic and social factors, and water excretion normally varies with a variable intake. Thus, a wide range of fluid intake can be normal. 17 However, when drinking and voiding significantly, interfere with the performance of the individual, the polyuria and polydipsia are no longer the result of "habit" drinking but probably are due to psychogenic causes or organic brain disease. Several observers have noted an association of diabetes insipidus, obsessional compulsive traits, and other symptoms suggesting hypothalamic malfunction, is I n some of these patients, damage to one or more hypothalamic centers m a y have resulted in the stimulation of thirst without affecting the secretion of A D H . Alternatively, damage to certain loci in the central nervous system

Volume 73

Number 6

may have interfered with the reception of stimuli that indicate satiation of thirst. Both circumstances cause neurogenic polydipsia. Because polyuria and polydipsia can result from true diabetes insipidus, hypothalamic damage that alters thirst but not ADH release, nephrogenic diabetes insipidus, or psychogenically determined poIydipsia, various diagnostic procedures are needed to determine the cause of these symptoms. Deprivation of water causes only a small increase in the osmolality of the urine of children with diabetes insipidus or nephrogenic diabetes insipidus unless severe dehydration and an altered glomerutar filtration rate supervene. The patient with diabetes insipidus responds appropriately to administration of vasopressin, but the patient with nephrogenic diabetes insipidus does not. A patient with polydipsia due to a damaged hypothalamic center, which is concerned with the perception of thirst satiation, responds to the administration of nicotine by producing a more concentrated urine if the hypothalamic centers needed for production of ADH are intact. Similarly, the individual who drinks excessively because of a hypothalamic lesion that stimulates thirst also increases release of ADH when given nicotine. I9 The psychogenic water drinker has no organic brain disease and responds to administration of nicotine, water deprivation, and administration of vasopressin. None of these tests permits differentiation between the patient who drinks compulsively because of a psychogenic need and the patient whose thirst is the result of a hypothalamic lesion that either has stimulated a center involved in thirst perception or has destroyed a center which normally signals satiation of thirst. These two conditions can be differentiated, therefore, only by history and by an understanding of the psychodynamics of psychogenic polydipsia. Primary polydipsia has been of interest to investigators chiefly because of the difficulty in differentiating it from diabetes insipidus. Whereas it usually is assumed that primary polydipsia has a psychogenic cause,

Primary polydips{a

849

the psychodynamic background of the illness has not been extensively explored. De Wardenerla, 17 has studied adults who drink compulsively and has noted that they usually have no physical abnormalities but do have a history of many neurotic traits dating back to childhood, as well as a history of vague childhood illnesses. They are often ill as adults and are usually unhappily married. They may be hysterical or depressive because of a plethora of psychologic problems and are frequently compulsive eaters. Little has been written concerning primary polydipsia in children, because it seems to be a rare phenomenon. Some evidence indicates that the child with psychogenic polydipsia (compulsive water drinking) may be similar to the child with psychogenic hyperphagia (compulsive eating). W h e n t h e histories of these patients are compared with those of the compulsive eater, many similarities are noted. The obese child with psychogenic hyperphagia usually has an intense emotional involvement with one of the parents, usually the mother, and this parent generally has an exaggerated concern for the physical well being of the child. The parents often attempt to make up with attention what they are unable to give in affection. The child is used by the parents (or parent) as an object to fulfill their needs or to compensate for their failures and frustrations. As the mother of the obese child is frequently domineering and the father docile, parental discord is the rule. Defects of adaptation of the child are seen on many levels (emotional, social, and so forth), and his behavior is immature. The obese child is usually withdrawn and seclusive. He has a low frustration tolerance and reacts by withdrawing or by overt hostility. Compulsive eating often arises in reaction to some sort of traumatic emotional experience, such as a death in the family, parental separation, birth of a sibling, an operation, or hospitalization. 20 Both of the patients whose cases are presented herein had a serious organic illness prior to or at the onset of their compulsive drinking; both had domineering mothers; both came from

850

Stevko, BaIsley, and Segar

homes characterized by parental discord; both had marginal intellectual endowments; and both have difficulty in peer relationships. The primary polydipsia observed in one or both of the children described in this report may be psychogenic; the psychosocial history supports this position. Like the children who eat compulsively, both patients adapted poorly and both were withdrawn and seclusive. The child with compulsive eating feels helpless and inadequate and attempts to compensate for these feelings by flights into fantasies or by daydreaming. The fantasies may be aggressive and reflect his hostility and anger toward his environment. These symptoms were observed clinically and confirmed by psychologic studies in the cases herein presented. T h e compulsion of water drinking is not meaningless but operates by the mechanism of displacement, substitution, or symbolism. The anxiety aroused by the unconscious impulses of hostility is partially alleviated through the compulsive act. Thus, the hostility and anger demonstrated by the 2 children and the anxiety produced by these feelings are partially relieved by the act of drinking watery 1 Drinking is a way of saying " I need your love and understanding, please satisfy my thirst."

The ]ournal of Pediatrics December I968

although each demonstrated the ability to concentrate urine and to release A D H normally, their excessive thirst cannot necessarily be attributed to psychogenic factors. Both also had organic disease involving the central nervous system and may have had residual hypothalamic damage, which in turn may have resulted in stimulation of one of the hypothalamic centers that increase thirst or in destruction of a thirst--inhibiting (satiation) center, thereby producing neurogenie polydipsia. In the final analysis, although the data may suggest a psychogenic cause, the possibility that the increased drinking is t h e result of an organic lesion cannot be excluded. Diabetes insipidus cannot be diagnosed solely on the basis of clinical observation even though the patient has a proved organic disease that is known to interfere with synthesis or release of ADH. In any child with the symptoms of diabetes insipidus, a water-withholding test should be done, and when possible, measurement of blood A D H should be carried out for confirmation of the diagnosis. Dr. Nancy Roeske, Director of the Riley Hospital Child Guidance Clinic, rendered helpful advice.

CONCLUSIONS Both children have diseases that cause diabetes insipidus. In both, the diabetes insipidus probably was transient and primary polydipsia subsequently developed. Psychologic testing disclosed that each child had an intellectual endowment in the dull-normal range and that each displayed increased dependency, as well as a passive-aggressive personality pattern. The combination of this type of personality disorder with excessive ingestion through the oral route indicates an association with obesity. Both children had obese mothers, and both children also might have become obese had their psychodynamics not been altered by organic illnesses that caused the substitution of water for food. Although both of these children had personality disorders similar to those observed in patients with psychogenic obesity and

REFERENCES

I. Rogge, J. D., Moore, W. W., Segar, W. E., and Fasola, A. F.: Effect of +G, and +G, acceleration on peripheral venous AD}I levels in humans, J. Appl. Physiol. 23: 870, 1967. 2. Segar, W. E., and Moore, W. W.: Regulation of ADH release in man. I. Effect of change in position and ambient temperature on blood ADH levels, J. Clln. Invest. (In press. ) 3. Adolph, E. F., Barker, J. P., and Hoy, P A.: Multiple factors in thirst, Am. J. Physiol. 178: 538, 1954. 4. Fitzsimons, J. T.: Drinking by rats depleted of body fluid without increase in osmotic pressure, J. Physiol. (London) 159': 297, 1961. 5. Fitzsimons, J. T.: The hypothalamus and drinking, Brit. M. Bull. 22: 232, 1966. 6. Grossman, S. P . : Direct adrenergic and cholinergic stimulation of hypothalamic mechanisms, Am. J~ Physiol. 202: 872, 1962. 7. Grossman, S. P.: Effects of adrenergic and cholinergic blocking agents on hypothalamic mechanisms, Am. J. Physiol. 202: 1230, 1962.

Volume 73 Number 6

8. Nothnagel, H.: Durst und Polydipsie, Virchows Arch. path. Anat. 86: 435, 1881. 9. Bailey, P., and Bremer, F.: Experimental diabetes insipidus, Arch. Intern. Med. 28: 773, 1921. 10. Andersson, B., Cale, C. C., and Sundsten, J. W.: Thirst, in Wayner, M. J., editor: Proceedings of the First International Symposium on Thirst in the Regulation of Body Water, New York, 1964, Pergamon Press, Inc., p. 361. 11. Smith, R. W., and McCann, S. M.: Alterations in food and water intake after hypothalamic lesions in the rat, Am. J. Physiol. 203: 366, 1962. 12. Stevenson, J. A. F., Welt, L. G., and Orloff, J.: Abnormalities of water and electrolyte metabolism in rats with hypothalamic lesions, Am. J. PhysioI. I61: 35, 1950. 13. De Wardener, H. E.: Polyurla, J. Chronic Dis. 11: 199, 1960. 14. Gilbert, G, J.: The subcommissural organ: A regulator of thirst, Am. J. Physiol. 191: 243, 1957.

Primary polydipsla

85 1

15. Andersson, B., and McCann, S. M.: The effect of hypothalamic lesions on the water intake of the dog, Acta physiol, scandinav. 35: 3t2, I956. 16. Falk, J. L.: Production of polydipsia in normal rats by an intermittent food schedule, Science 133: 195, 1961. 17. De Wardener, H. E.: The kidney: An outline of normal and abnormal structure and function, ed. 2, Boston, 1961, Little, Brown & Company, p. 276. 18. Barton, R.: Diabetes insipidus and obsessional neurosis: A syndrome, Lancet 1: 133, 1965. 19. Dingman, J. F., Benirschke, K., and Thorn, G. W.: Studies of neurohypophyseal function in man, Am. J. Med. 23: 226, 1957. 20. Bruch, H.: Obesity, Pedlat. Clin. North America p. 613, I958. 21. Bakwln, H., and Bakwln, R.: Obesity: Clinical management of behavior disorders in children, Philadelphia, 1953, W. B. Saunders Company.