The successful management of endocrine diseases is greatly helped by the complete understanding of the underlying pathology. The knowledge about the molecular genetics contributes immensely in the appropriate identification of the causative factors of the diseases and their subsequent management. The fields of nephrology and endocrinology are also interrelated to a large extent. Besides performing the secretory functions, the renal tissue also acts as target organ for many hormones such as antidiuretic hormone (ADH), atrial natriuretic peptides (ANP), and aldosterone. Understanding the molecular genetics of these hormones is important because the therapeutic interventions in many of these conditions is related to shared renal and endocrine functions, including the anemia of renal disease, chronic kidney disease, mineral bone disorders, and hypertension related to chronic kidney disease. Their understanding and in-depth knowledge is very essential in designing and formulating the therapeutic plans and innovating new management strategies. However, we still have to go a long way in order to completely understand the various confounding causative relationships between the pathology and disease of these reno-endocrinal manifestations.

Rickets is an important problem even in countries with adequate sun exposure. The causes of rickets/osteomalacia are varied and include nutritional deficiency, especially poor dietary intake of vitamin D and calcium. Non-nutritional causes include hypophosphatemic rickets primarily due to renal phosphate losses and rickets due to renal tubular acidosis. In addition, some varieties are due to inherited defects in vitamin D metabolism and are called vitamin D dependent rickets. This chapter highlights rickets/osteomalacia related to vitamin D deficiency or to inherited defects in vitamin D metabolism. Hypophosphatemic rickets and rickets due to renal tubular acidosis are discussed in other sections of the journal.

Hypophosphatemic rickets is a disorder of bone mineralization caused due to defects (inherited/acquired) in the renal handling of phosphorus. This group includes varied conditions, X-linked hypophosphatemic rickets being the most common inheritable form of rickets. The other common forms are autosomal dominant hypophosphatemic rickets and tumor-induced osteomalacia. Although these conditions exhibit different etiologies, increased phosphatonins form a common link among them. Fibroblast growth factor 23 (FGF23) is the most widely studied phosphatonin. Genetic studies tend to show that the phosphorus homeostasis depends on a complex osteo-renal axis, whose mechanisms have been poorly understood so far. Newer disorders are being added as the mechanisms in this axis get discovered. This review focuses on the clinical, biochemical, genetic features and management of hypophosphatemic disorders leading to defective mineralization.

Hyponatremia is the most common electrolyte abnormality in hospitalized patients. Its treatment is based not only on extracellular fluid volume status of patients but also on its pathogenetic mechanisms. Conventional treatment of hyponatremia like fluid restriction, which is useful in euvolemic and hypervolemic hyponatremia, has very poor patient compliance over long term. Vasopressin receptor antagonists (Vaptans) are a new group of nonpeptide drugs which have been used in various clinical conditions with limited success. Whereas conivaptan is to be administered intravenously, the other vaptans like tolvaptan, lixivaptan, and satavaptan are effective as oral medication. They produce aquaresis by their action on vasopressin type 2 (V2R) receptors in the collecting duct and thus increase solute free water excretion. Vaptans are being used as an alternative to fluid restriction in euvolemic and hypervolemic hyponatremic patients. Efficacy of vaptans is now well accepted for management of correction of hyponatremia over a short period. However, its efficacy in improving the long-term morbidity and mortality in patients with chronic hyponatremia due to cirrhosis and heart failure is yet to be established. Vaptans have not become the mainstay treatment of hyponatremia yet.

The pineal gland is a tiny endocrine gland whose physiologic role has been the focus of much research and much more speculation over the past century. This mini-review discusses recent findings which correlate melatonin and renal physiology, and postulates the presence of a "reno-pineal axis." Drawing lessons from comparative endocrinology, while quoting human data, it advocates the need to study the "reno-pineal axis" in greater detail.

Severe growth retardation (below the third percentile for height) is seen in up to one-third children with chronic kidney disease. It is thought to be multifactorial and despite optimal medical therapy most children are unable to reach their normal height. Under-nutrition, anemia, vitamin D deficiency with secondary hyperparathyroidism, metabolic acidosis, hyperphosphatemia, renal osteodystrophy; abnormalities in the growth hormone/insulin like growth factor system and sex steroids, all have been implicated in the pathogenesis of growth failure. Therapy includes optimization of nutritional and metabolic abnormalities. Failure to achieve adequate height despite 3-6 months of optimal medical measures mandates the use of recombinant GH (rGH) therapy, which has shown to result in catch-up growth, anywhere from 2 cm to 10 cm with satisfactory liner, somatic and psychological development.

There are several interactions between thyroid and kidney functions in each other organ's disease states. Thyroid hormones affect renal development and physiology. Thyroid hormones have pre-renal and intrinsic renal effects by which they increase the renal blood flow and the glomerular filtration rate (GFR). Hypothyroidism is associated with reduced GFR and hyperthyroidism results in increased GFR as well as increased renin - angiotensin - aldosterone activation. Chronic kidney disease (CKD) is characterized by a low T3 syndrome which is now considered a part of an atypical nonthyroidal illness. CKD patients also have increased incidence of primary hypothyroidism and subclinical hypothyroidism. The physiological benefits of a hypothyroid state in CKD, and the risk of CKD progression with hyperthyroidism emphasize on a conservative approach in the treatment of thyroid hormone abnormalities in CKD. Thyroid dysfunction is also associated with glomerulonephritis often by a common autoimmune etiology. Several drugs could affect both thyroid and kidney functions. There are few described interactions between thyroid and renal malignancies. A detailed knowledge of all these interactions is important for both the nephrologists and endocrinologists for optimal management of the patient.

Sexual and gonadal dysfunction/infertility are quite common in patients with chronic kidney disease. Forty percent of male and 55% of female dialysis patients do not achieve orgasm. The pathophysiology of gonadal dysfunction is multifactorial. It is usually a combination of psychological, physiological, and other comorbid factors. Erectile dysfunction in males is mainly due to arterial factors, venous leakage, psychological factors, neurogenic factors, endocrine factors, and drugs. Sexual dysfunction in females is mainly due to hormonal factors and manifests mainly as menstrual irregularities, amenorrhea, lack of vaginal lubrication, and failure to conceive. Treatment of gonadal dysfunction in chronic kidney disease is multipronged and an exact understanding of underlying pathology is essential in proper management of these patients.

Recombinant human erythropoietin (rhEPO) is arguably the most successful therapeutic application of recombinant DNA technology till date. It was isolated in 1977 and the gene decoded in 1985. Since then, it has found varied applications, especially in stimulating erythropoiesis in anemia due to chronic conditions like renal failure, myelodysplasia, infections like HIV, in prematurity, and in reducing peri-operative blood transfusions. The discovery of erythropoietin receptor (EPO-R) and its presence in non-erythroid cells has led to several areas of research. Various types of rhEPO are commercially available today with different dosage schedules and modes of delivery. Their efficacy in stimulating erythropoiesis is dose dependent and differs according to the patient's disease and nutritional status. EPO should be used carefully according to guidelines as unsolicited use can result in serious adverse effects. Because of its capacity to improve oxygenation, it has been abused by athletes participating in endurance sports and detecting this has proved to be a challenge.

Nephrolithias is a common problem in populations around the world, and contribute significantly to the development of end stage renal disease. It is a matter of debate whether the metabolic factors responsible for renal stone formation are similar or variable in different populations around the globe. This review discusses the influence of different metabolic and dietary factor, and some other co-morbid conditions on the etiopathogenesis Nephrolithiasis. Evaluation and medical management of Nephrolithiasis is summarized in the later part of the article.

Kidney stone is a common clinical problem faced by clinicians. The prevalence of the disease is increasing worldwide. As the affected population is getting younger and recurrence rates are high, dietary modifications, lifestyle changes, and medical management are essential. Patients with recurrent stone disease need careful evaluation for underlying metabolic disorder. Medical management should be used judiciously in all patients with kidney stones, with appropriate individualization. This chapter focuses on medical management of kidney stones.

The burden of cardiovascular disease (CVD) is increasing worldwide. The increase in the burden is a major concern in developing countries like India. It is well-established that hypertension and dyslipidemia are the two major contributing risk factors for CVD. Various epidemiological studies have shown the prevalence of the co-existence of hypertension and dyslipidemia, in the range of 15 to 31%. The co-existence of the two risk factors has more than an additive adverse impact on the vascular endothelium, which results in enhanced atherosclerosis, leading to CVD. This review emphasizes on the 'co-existence and interplay of dyslipidemia and hypertension'. The authors have termed the co-existence as, 'LIPITENSION'. The term LIPITENSION may help clinicians in easy identification and aggressive management of the two conditions together, ultimately preventing future cardiovascular events.

Protein-energy wasting (PEW) is common in patients with chronic kidney disease (CKD). PEW is one of the strongest predictors of mortality in patients with CKD. The International Society of Renal Nutrition and Metabolism (ISRNM) expert panel has defined PEW as a, "state of decreased body stores of protein and energy fuels (body protein and fat masses)". The ISRNM panel has also proposed diagnostic criteria of PEW with four categories. Cachexia is a severe form of PEW. The proposed causes of PEW are multi-factorial and include nutritional and non-nutritional mechanisms. The literature indicates that PEW can be mitigated or corrected with an appropriate diet and enteral nutritional support that targets dietary protein intake. Dietary requirements and enteral nutritional support must also be considered in patients with CKD and diabetes mellitus and in children with CKD, in addition to dialysis patients. Features of ideal dietary supplement have also been discussed. Dietary interventions such as enteral feeding with high-protein meals or supplements might improve the nutritional status and outcomes in dialysis patients.

Nowadays, an increasing number of patients get admitted with polytrauma, mainly due to road traffic accidents. These polytrauma victims may exhibit associated renal injuries, in addition to bone injuries and injuries to other visceral organs. Nevertheless, even in cases of polytrauma, renal tissue is hyperfunctional as part of the normal protective responses of the body to external insults. Both polytrauma and renal injuries exhibit widespread renal, endocrine, and metabolic responses. The situation is very challenging for the attending anesthesiologist, as he is expected to contribute immensely, not only in the resuscitation of such patients, but if required, to allow the operative procedures in case of life-threatening injuries. During administration of anesthesia, care has to be taken, not only to maintain hemodynamic stability, but equal attention has to be paid to various renal protection strategies. At the same time, various renoendocrine manifestations have to be taken into account, so that a judicious use of anesthesia drugs can be made, to minimize the renal insults.

Primary hyperparathyroidism (PHPT) is associated with nephrolithiasis and nephrocalcinosis. Hypercalciuria is one of the multiple factors that is implicated in the complex pathophysiology of stone formation. The presence of a renal stone (symptomatic or asymptomatic) categorizes PHPT as symptomatic and is an indication for parathyroid adenomectomy. Progression of nephrocalcinosis is largely reversible after successful surgery, but the residual risk persists. PHPT is also associated with declining renal function. In case of asymptomatic mild PHPT, annual renal functional assessment is advised. Guidelines suggest that an estimated glomerular filtration rate (eGFR) < 60 ml / minute / 1.73 m ² is an indication for parathyroid adenomectomy. This article discusses how to monitor and manage renal stones and other related renal parameters in case of PHPT.

Objective: Vitamin D deficiency is an unrecognized epidemic and a common health problem worldwide. This study was conducted to evaluate the vitamin D status in children living in Jeddah, Saudi Arabia and to study its relation to various variables. Materials and Methods: A cross-sectional study was conducted in the pediatric clinic in Jeddah Clinic Hospital-Kandarah, Jeddah, KSA, from October through December 2010, in which 510 healthy children aged 4-15 years were enrolled. Serum calcium, phosphorus, alkaline phosphatase and 25-hydroxyvitamin D [25(OH)D] were measured. Dietary vitamin D intake and duration of daily sunlight exposure were determined. 25(OH)D levels <20 ng/mL and <7 ng/mL were defined as relative and severe vitamin D deficiency, respectively. Results: The mean concentration of 25(OH)D was 13.07 ± 7.81 ng/mL. Seventy subjects (13.72%) had normal 25(OH)D level ranging 20-70 ng/mL. Three hundred (58.82%) had relative 25(OH)D deficiency and 140 (27.45%) had severe deficiency (P=0.000). 220 (43.14%) subjects were males and 290 (56.86%) were females having a statistically significant higher incidence of 25(OH)D deficiency (P=0.019). 54.9% were Saudis, 27.45% were Yemenis and 11.76% were Egyptians. Saudis and Yemenis were more subjected to 25(OH)D deficiency in comparison to Egyptians and other nationalities (P=0.01). There were significant inverse correlations between 25(OH)D levels and bony aches (P=0.000). 56.25% of asymptomatic children had vitamin D deficiency (P=0.000). Duration of sunlight exposure and daily intake of vitamin D had significant effects on serum level of vitamin D (P=0.000). Conclusions: A high prevalence of vitamin D deficiency in children living in Jeddah was observed in this study. Vitamin D supplementation of food products can prevent vitamin D deficiency in these children.

Background : Vitamin D [(25(OH)D] deficiency and insufficiency is common in patients with chronic kidney disease (CKD). 25(OH)D has been found to have beneficial effects on bone, cardiovascular and immune functions. There are little data about vitamin D levels in Indian patients on dialysis. This study was undertaken to determine the vitamin D status of Indian CKD patients on hemodialysis. Materials and Methods : We included 45 patients on maintenance hemodialysis coming to Medanta, Medicity, Gurgaon. 25(OH)D levels were measured with radioimmunoassay (Diasorin) method and parathyroid hormone (PTH) was measured using electrochemiluminiscence immunoassay (ECLIA). Results : The mean age of patients was 55 ± 13 years. 32/45 (71%) were males. 23/45 (51%) were diabetics. The median duration of hemodialysis was 5.5 months (range 1-74 months). 33/45 (74%) patients were on thrice weekly hemodialysis. The mean level of vitamin D was 10.14 ± 8.7 ng/ml. Majority of the patients [43/45 (95.5%)] were either vitamin D deficient or had insufficient levels. 40/45 (88.9%) were vitamin D deficient (levels <20 ng/ml); of these, 29/40 (64.4%) had severe vitamin D deficiency (levels <10 ng/ml) and 3/45 (6.7%) had insufficient levels (20-30 ng/ml) of vitamin D. Only 2/45 (4.4%) patients had normal levels of vitamin D. 23/45 (51%) of patients were receiving calcitriol. The mean levels of serum calcium, phosphorus, alkaline phosphatase, and albumin were 8.8 ± 0.64 mg/dl, 5.0 ± 0.7 mg/dl, 126 ± 10.3 IU/l and 3.6 ± 0.62 g/dl, respectively. PTH levels ranged from 37 to 1066 pg/ml, and the median was 195.8 pg/ml. There was a weak correlation between 25(OH)D levels and weight, sex, hemoglobin, albumin, alkaline phosphatase, and presence of diabetes. There was, however, no correlation with duration of dialysis or PTH levels. Conclusion : Vitamin D deficiency and insufficiency are universal in our hemodialysis patients, with severe vitamin D deficiency in two-third of patients.

Aim: Deficiency of Vitamin D is prevalent in the general population, especially in Chronic Kidney Disease (CKD) patients. The exact prevalence of Vitamin D deficiency is unknown in post renal transplant recipients. The classical and non-classical effects of vitamin D deficiency are complicated by the use of steroids and calcineurin inhibitors (CNIs) in the renal transplant population. The aim of this study is to document the prevalence of Vitamin D deficiency in the post renal transplant population. Materials and Methods: A total of 51 renal transplant recipients under follow-up at Indraprastha Apollo Hospital, between June 2009 and March 2011, were enrolled in this study. Parathormone (PTH), 25(OH)-vitaminD3, calcium, and phosphate levels were determined in all the patients. The patients were then classified into different groups based on the severity of the Vitamin D deficiency, time since transplantation, and level of graft function. Results: Overall, four patients (8%) were vitamin D sufficient, 17 patients (33%) insufficient, 26 patients (51%) mildly deficient, and four (8%) severely deficient. The degree of deficiency did not differ with reference to the time since transplant or level of graft function. Sixty-nine percent had high PTH level, 22% were normal, and 9% had a low parathyroid hormone level. There was an inverse correlation between Vitamin D deficiency and serum PTH level. Conclusion: In this study, there was a high prevalence of vitamin D deficiency in renal transplant recipients. This did not get corrected, despite nutritional improvement or normalization of the glomerular filtration rate (GFR) post transplantation. Therefore, the study emphasizes routine evaluation and proper supplementation of Vitamin D in all post renal transplant patients.

Objective: Polycystic ovarian syndrome (PCOS) is a clinically heterogeneous endocrine disorder affecting up to 4-8% of women of reproductive age. The aim of this study was to evaluate the presence of microalbuminuria in women with PCOS and study its correlation with the various metabolic, clinical, and hormonal parameters. Materials and Methods: A cross-sectional study involving 69 PCOS women was carried out in a tertiary care center hospital. The diagnosis of PCOS was made according to the Rotterdam criteria. Blood samples were collected in the follicular phase of the menstrual cycle and analyzed for fasting luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL), 17-hydroxyprogesterone (17-OHP), total testosterone (T), glucose, insulin, and lipid profile. Urinary albumin was measured in the first void spot urine sample. Results: The mean age of the subjects was 22.0 ± 4.1 years and 21.8 ± 4.7 years in normoalbuminuric and microalbuminuric groups, respectively. Urinary albumin excretion (UAE) varied from 5 mg/l to 100 mg/ml, with a median of 5 mg/l. Microalbuminuria was observed in 17/69 (24.6%) of subjects. The mean UAE was 3.65 ± 4.44 mg/l in the normoalbuminuria group versus 45.29 ± 22.74 mg/l in the microalbuminuria group. Upon univariate analysis, hip circumference, diastolic blood pressure, and fasting blood glucose showed significant correlations with urinary albumin concentration (r = 0.264, 0.264, and 0.551, respectively; P = 0.028, 0.029, and 0.000, respectively). No association between UAE and the usual cardiovascular risk factors could be found upon regression analysis. Conclusion: About 24.6% of women with PCOS showed presence of microalbuminuria in the first void spot urine sample. Screening for the presence of microalbuminuria can help in early identification of a subset of PCOS women with a high risk for future CVD, who can be subjected to preventive strategies at the earliest. However, further studies are needed before recommending routine use of UAE in PCOS cases for the detection of CVD risk.

Context: Renal calculus disease has a lifetime recurrence rate of 80%. Protocol-based metabolic evaluation in high-risk subjects for recurrent renal stones reveals abnormalities in a large subset of subjects. However, such information is not available in Indian subjects. Aims: To evaluate the abnormalities by a protocol-based metabolic evaluation in patients at a high risk for recurrent renal stones. Settings and Design: Prospective, academic tertiary care center. Materials and Methods: Fifty North Indian patients (38 males and 12 females; mean age 38 ± 10.2 years) with recurrent or bilateral renal stones were evaluated. All subjects underwent a protocol-based evaluation involving estimation of serum total calcium, phosphorus, creatinine, albumin, iPTH, 25(OH)D ₃ , 1,25(OH) ₂ D ₃ , and a calcium load test. Estimation of daily urinary excretion of volume, oxalate, calcium, uric acid, and citrate, and urinary acidification studies were performed. Statistical Analysis Used: Descriptive statistics and t-test. Results: An underlying disorder was detected in 48 (96%) patients. Almost half had two or more metabolic abnormalities. The metabolic abnormalities detected were: Hypercalciuria 26 (52%) patients, renal hypercalciuria 16 (32%), absorptive hypercalciuria 6 (12%), unclassified hypercalciuria 4 (8%), hyperoxaluria 27 (54%), hyperuricosuria 9 (18%), distal renal tubular acidosis 4 (8%; 2 complete and 2 partial), primary hyperparathyroidism 3 (6%), and hypocitraturia 14 (n=18, 77%). In two patients, the etiology could not be detected. Conclusions: Protocol-based metabolic evaluation reveals metabolic abnormalities in majority of patients with nephrolithiasis. The spectrums of metabolic abnormalities are different in Indian subjects as compared to the western population.

Background: Hyponatremia is one of the commonest electrolyte disturbances encountered in medical wards and contributes to substantial morbidity and mortality. However, early recognition and management drastically alters prognosis. Therefore, this observational study was taken up to explore the clinical profile of hyponatremia. Aim: To assess the incidence and clinical profile of hyponatremia in medically ill patients. Materials and Methods: This observational study was conducted in the medical ward of a tertiary care hospital from March 2010 to April 2011. All patients underwent routine hemogram, blood biochemistry, serum electrolytes, thyroid function tests, and morning serum cortisol estimation. This was followed by a plasma and urinary osmolality determination (osmometer 800 CL) as well as urinary sodium estimation. Patients were diagnosed to have syndrome of inappropriate antidiuretic hormone secretion (SIADH) if they satisfied the Bartter and Schwartz criteria. Results: 201 patients (16.4%) had a serum Na < 135 meq/l. There were 126 (62.69%) male patients and 75 (37.31%) female patients. Severe hyponatremia (Na < 120 meq/l) was detected in 30 patients (2.4%). The largest group of hyponatremic patients were euvolemic [102 (50.74%)], followed by hypervolemic [54 (26.86%)] and hypovolemic [45 (22.4%)]. Sixty-six patients fulfilled the criteria for SIADH. The most common underlying predisposing factor for hyponatremia in our case series was fluid loss by vomiting/diarrhea. During the hospital stay, 13.5% (15/201) hyponatremic patients died, while the corresponding figure in normonatremic patients was 8.5% (87/1020). Conclusion: The incidence of hyponatremia in our series was higher than values mostly reported in western literature. Euvolemic hyponatremia was the most common type, a significant fraction of which is SIADH.

The hunchback has long been a symbol of revilement in art and literature. This write up tries to find the cause of the deformity into two iconic hunchbacks in literature, Manthara and Quasimodo.

A 67-year-old female was admitted to the hospital with a history of lethargy, memory impairment, confusion, anorexia and gait imbalance for 2 weeks duration. She did not have any history of fall or head injury. She had total hip replacement 1 year back and was on orthopedic follow-up. Magnetic resonance imaging (MRI) on admission revealed no focal abnormalities. Routine biochemistry detected hypercalcemia, and she was treated with I/V fluid, diuretics and glucocorticoids. She was screened thoroughly to exclude occult malignancy. After 7 days of admission, a follow-up orthopedic prescription revealed that she was getting inj. Arachitol 6 lac units every week for last 3 months. On the 9 ^th day of admission, she was detected to have very high serum 25(OH) vitamin D level (254.70 ng/ml). Patient was discharged after 2 weeks after her serum calcium came down to normal range with the advice of no dietary calcium and vitamin D intake. Her 25(OH) vitamin D level remained high for the next 6 months. Now she is completely asymptomatic and her serum 25(OH) D is normal.

Gitelman's syndrome is an inherited tubulopathy affecting thiazide-sensitive sodium chloride cotransporter, which manifests with hypokalemic alkalosis, hypomagnesemia, and hypocalciuria. Recently few cases have been described having an association of Gitelman's syndrome with pituitary abnormalities on imaging, though with normal hormonal status. We describe the first case of an adult patient having Gitelman's syndrome and hypopituitarism with abnormal pituitary imaging. She presented to us with hypotension, hypokalemia, hypomagnesemia with alkalosis, hypothyroidism, hypocortisolism, and hypogonadism. She was treated with replacement of electrolytes and hormones, to which she showed an excellent response.

Bartter syndrome is a rare hereditary (autosomal recessive) salt-losing tubulopathy characterized by hypokalemia, hypochloremia, metabolic alkalosis, and normal blood pressure with hyperreninemia, The underlying renal abnormality results in excessive urinary losses of sodium, chloride, and potassium. We report a case of a four-month-old infant with neonatal Bartter syndrome, who presented only with status epilepticus. To the best of our present knowledge, there is no reported case of Bartter syndrome who presented with status epilepticus.

Emphysematous pyelonephritis, though uncommon, is a severe necrotizing kidney infection common in patients with diabetes. Surgical treatment has been advocated as the treatment of choice in most of the patients. We present the clinical course of an elderly lady who presented with emphysematous pyelonephritis and was successfully managed with medical treatment despite the presence of adverse prognostic factors like acute renal failure and thrombocytopenia.

Sheehan's syndrome occurs as a result of ischemic pituitary necrosis secondary to severe postpartum bleeding. It is one of the most common causes of hypopituitarism, characterized by variable clinical presentation. Acute kidney injury occurs rarely in Sheehan's syndrome and most of the cases have been found to be precipitated by rhabdomyolysis. We here present a case of Sheehan's syndrome with acute kidney injury where theprecipitating cause was chronic hypocortisolemia. We believe this is the first reported case of Sheehan's syndrome in which acute kidney injury was precipitated by adrenal insufficiency.

Central giant cell granulomas (CGCGs) are uncommon but the most aggressive benign intraosseous tumors of jaws, with an unpredictable outcome. They account for less than 7% of all benign jaw lesions, with a female to male ratio of about 2:1. The classical "brown tumor" is commonly seen in the long bones, pelvis, and ribs. Facial bone involvement is rare and usually appears as solitary or multilocular soap bubble like radiolucencies. CGCGs are traditionally treated by both surgical and intralesional injection, with a variable recurrence rate. Here, we report a 12-year-old female patient with mandibular brown tumor as a first sign of secondary hyperthyroidism induced due to vitamin D deficiency and hypocalcemia.