Fanconi syndrome, diabetes insipidus, and acute kidney injury due to tenofovir disoproxil fumarate: A case report.

BACKGROUND: Tenofovir disoproxil fumarate is widely used in Botswana as part of the first-line antiretroviral regimen in the 'Treat All' strategy implemented in 2016 by the Ministry of Health. Its use has been associated with several uncommon adverse renal effects, though rarely all in conjunction or without the combined use of protease inhibitors. CASE PRESENTATION: A 49-year-old woman living with HIV whose viral load is suppressed on tenofovir disoproxil fumarate, lamivudine, and dolutegravir presented with 1 day of generalized weakness and myalgia causing an inability to ambulate. This was associated with nausea and vomiting and profound fatigue. She was found to have an acute kidney injury, non-anion-gap metabolic acidosis, hypernatremia, hypokalemia, and hypophosphatemia. Urinalysis revealed pyuria with white blood cell casts, glucosuria, and proteinuria. The diagnosis was made of tenofovir-induced nephrotoxicity. The tenofovir was discontinued, and the patient was initiated on intravenous fluids and electrolyte and bicarbonate supplementation with improvement in her symptoms and laboratory values. CONCLUSIONS: This report suggests the possibility of severe tenofovir-induced nephrotoxicity with combined acute kidney injury, Fanconi syndrome, and nephrogenic diabetes insipidus in the absence of other provoking factors such as use with protease inhibitors or advanced HIV disease, chronic kidney disease, and age. With its wide use in Botswana and other countries, health-care providers should have a high index of suspicion for tenofovir-induced nephrotoxicity for HIV patients on tenofovir with deranged renal function tests and electrolytes.

Lithium treatment inhibits renal GSK-3 activity and promotes cyclooxygenase 2-dependent polyuria.

The use of LiCl in clinical psychiatry is routinely complicated by overt nephrogenic diabetes insipidus (NDI), the mechanism of which is incompletely understood. In vitro studies indicate that lithium can induce renal medullary interstitial cell cyclooxygenase 2 (COX2) protein expression via inhibition of glycogen synthase kinase-3beta (GSK-3beta). Both COX1 and COX2 are expressed in the kidney. Renal prostaglandins have been suggested to play an important role in lithium-induced polyuria. The present studies examined whether induction of the COX2 isoform contributes to LiCl-induced polyuria. Four days after initiation of lithium treatment in C57 BL/6J mice, urine volume increased in LiCl-treated mice by fourfold compared with controls (P < 0.0001) and was accompanied by decreased urine osmolality. This was temporally associated with increased renal COX2 protein expression and increased urinary PGE(2) excretion, whereas COX1 levels remained unchanged. COX2 inhibition significantly blunted lithium-induced polyuria (P < 0.0001) and reduced urinary PGE(2) levels. Lithium-associated polyuria was also seen in COX1-/- mice and was associated with increased urinary PGE(2). COX2 inhibition completely prevented polyuria and PGE(2) excretion in COX1-/- mice, suggesting that COX2, but not COX1, plays a critical role in lithium-induced polyuria. Lithium also induced renal medullary COX2 protein expression in congenitally polyuric antidiuretic hormone (AHD)-deficient rats, demonstrating that lithium-induced COX2 protein expression is not secondary to altered ADH levels or polyuria. Lithium also decreased renal medullary GSK-3beta activity, and this was temporally related to increased COX2 expression in the kidney from lithium-treated mice, consistent with a tonic in vivo suppression of COX2 expression by GSK-3 activity. In conclusion, these findings temporally link decreased GSK-3 activity to enhanced renal COX2 expression and COX2-derived urine PGE(2) excretion. Suppression of COX2-derived PGE(2) blunts lithium-associated polyuria.

Prenatal exposure to ethanol causes partial diabetes insipidus in adult rats.

Chronic consumption of ethanol in adult rats and humans leads to reduced AVP-producing neurons, and prenatal ethanol (PE) exposure has been reported to cause changes in the morphology of AVP-producing cells in the suprachiasmatic nucleus of young rats. The present studies further characterize the effects of PE exposure on AVP in the young adult rat, its hypothalamic synthesis, pituitary storage, and osmotically stimulated release. Pregnant rats were fed a liquid diet with 35% of the calories from ethanol or a control liquid diet for days 7-22 of pregnancy. Water consumption and urine excretion rate were measured in the offspring at 60-68 days of age. Subsequently, the offspring were infused with 5% NaCl at 0.05 ml.kg(-1).min(-1) with plasma samples taken before and at three 40-min intervals during infusion for measurement of AVP and osmolality. Urine output and water intake were approximately 20% greater in PE-exposed rats than in rats with no PE exposure, and female rats had a greater water intake than males. The relationship between plasma osmolality and AVP in PE-exposed rats was parallel to, but shifted to the right of, the control rats, indicating an increase in osmotic threshold for AVP release. Pituitary AVP was reduced by 13% and hypothalamic AVP mRNA content was reduced by 35% in PE-exposed rats. Our data suggest that PE exposure can cause a permanent condition of a mild partial central diabetes insipidus.

A compartmental model predicts that dietary potassium affects lithium dynamics in rats.

Lithium is the treatment of choice for manic depression, but therapy often results in nephrogenic diabetes insipidus and lithium intoxication. To investigate the effects of dietary potassium on potential side effects of lithium therapy, a mathematical model was built using the modeling program SAAM (Simulation, Analysis, And Modeling). Experimental data modeled were from adult male Sprague-Dawley rats fed diets with or without lithium and one of three levels of potassium for 17 d. A five-compartment model of lithium dynamics was built that was consistent with data from rats fed a lithium-containing diet adequate in potassium. This model was then compared with data from rats fed the other two lithium-containing diets. The model predicts that both the fractional transfer coefficient and rate of transport of lithium to the serum compartment from the kidney compartment are lower in rats fed the potassium-adequate diet than in those fed the potassium-deficient diet, and even lower in those fed the potassium-supplemented diet. In addition, fractional transfer coefficients into the serum compartment from the sampled and simulated tissue compartments changed differently with time depending on the amount of dietary potassium. The model also predicts that there would be less accumulation of lithium in the kidney, sampled tissue and simulated tissue compartments with supplemental dietary potassium. The model suggests that potassium supplementation, after a 7-d delay, protects against nephrogenic diabetes insipidus and the potentially toxic accumulation of lithium by decreasing the reabsorption of lithium from the kidneys and increasing lithium efflux from the tissues.

[Lithium-induced chronic water-metabolism disorder (nephrogenic diabetes insipidus)]. / Lithium által okozott maradandó vízanyagcsere zavar (nephrogen diabetes insipidus).

Lithium may induce all clinical physiological abnormalities of the polydipsia- polyuria syndrome. Authors describe a 61-year-old woman patient in whom permanent disturbance of the water metabolism, nephrogenic diabetes insipidus (NDI) was caused by lithium treatment, lasting longer than 10 years. The partial resistance of the fluid disturbance to vasopressin has been investigated by the administration of supramaximal doses of dDAVP. Considering the known antidiuretic effect of indomethacin, authors compared antidiuruetic activity of indomethacin and piroxicam (Hotemin) by studying standard parameters of water metabolism/free water clearance ect.) It was found that piroxicam, on mg basis a more effective antiinflammatory compound, was less antidiuretic then indomethacin. It was concluded, that there is no close parallelism between the structure and antiinflammatory and antidiuretic activity of nonsteroid antiinflammatory drugs. In the opinion of authors nonsteroid antiinflammatory drugs may have a role in the treatment of lithium-induced NDI, though, the establishment of the safety use of such therapy requires further studies.

Selective cell death of magnocellular vasopressin neurons in neurohypophysectomized rats following chronic administration of vasopressin.

Regeneration and functional recovery of the hypothalamoneurohypophysial system (HNS) in neurohypophysectomized rats treated with either saline or vasopressin (VP) were analyzed utilizing specific immunohistochemical and physiological measures. Neural lobe ablation combined with VP administration precipitated a profound diabetes insipidus (following cessation of VP delivery) that persisted for the duration of the experiment. Diabetes insipidus was correlated with a drastic reduction in the number of VP-positive neurons in magnocellular hypothalamic nuclei. In contrast, large numbers of oxytocin (OT)-positive neurons survived neurohypophysectomy in VP-treated neurohypophysectomized rats; OT neurons accounted for the vast majority of magnocellular profiles observed in Nissl-counterstained sections. VP-immunoreactive fibers could be observed in limited quantities in the external lamina of the median eminence of VP-treated neurohypophysectomized rats, with little staining evident in the internal lamina. Saline-treated neurohypophysectomized rats exhibited the recovery of antidiuretic function characteristically seen following this lesion, with evidence of survival of considerable numbers of VP and OT neurons and median eminence hypertrophy. Both the internal and external laminae of the median eminence were densely innervated by large-caliber VP and OT fibers. Sham-operated animals receiving VP treatment did not show any long-term deficit in water metabolism, changes in the complement of VP or OT perikarya in hypothalamus, or changes in the innervation of the median eminence. Results indicate that VP treatment following neurohypophysectomy results in extensive retrograde degeneration of magnocellular VP neurons without affecting the survival of OT cells.

Attenuation of the lithium-induced diabetes-insipidus-like syndrome by amiloride in rats.

The effect of amiloride on lithium-induced polydipsia and polyuria and on the lithium concentration in the plasma, brain, kidney, thyroid and red blood cells was investigated in rats, chronically treated with LiCl. Amiloride reduced the drinking and urine volume of rats in an acute (6 or 12 h) and a subacute (3 days) experiment. 6 h after the administration of amiloride, a reduction was observed in the lithium content of the renal medulla but not in the other organs studied. At 12 h, all the tissues showed a slight increase in lithium levels. After 3 days of combined treatment, a marked elevation in plasma and tissue lithium levels accompanied a reduction in water intake. In all the experiments, the attenuation of the lithium-induced diabetes-insipidus-like syndrome by amiloride was accompanied by a reduction of the ratio between the lithium concentration in the renal medulla and its levels in the blood and an elevation in the plasma potassium level. It is concluded that acute amiloride administration to lithium-treated patients suffering from polydipsia and polyuria might relieve these patients but prolonged amiloride supplementation would result in elevated lithium levels and might be hazardous.

Nephrogenic diabetes insipidus due to demethylchlortetracycline hydrochloride in a child.

Nephrogenic diabetes insipidus occurred in a 7-year-old child who had received a high dose of demethylchlortetracycline hydrochloride (DMC). The patient had a relatively elevated urinary sodium concentration in addition to isosthenuria. The nephrogenic diabetes insipidus was completely reversible within one month after cessation of DMC administration.