Tumor-induced hypophosphatemia

Significant hypophosphatemia is commonly due to Vitamin D deficiency. Any sporadic onset of hypophosphatemia in adults warrants workup to identify alternate causes. Hypophosphatemia may also be the only manifestation of an occult malignancy. A high index of clinical suspicion can help diagnose such conditions in early stages. Prompt treatment of the cause can correct this biochemical abnormality. We describe a case report of a woman presenting with severe hypophosphatemia and osteomalacia, leading eventually to the diagnosis of a phosphaturic mesenchymal tumor of the temporo-occipital bone. Surgical resection of tumor led to normalization of the biochemical parameters as well as a complete clinical recovery.

Renal disease masquerading as pyrexia of unknown origin

Pyrexia of unknown origin is a challenging clinical problem. Infections, malignancies, and connective tissue diseases form the major etiologies for this condition. We report a case of a 57-year-old diabetic male who presented with fever of unknown origin for several months. The course of investigations led to a kidney biopsy which clinched the cause of his fever as well as the underlying diagnosis. The light microscopy findings of expansile storiform fibrosis with a dense inflammatory infiltrate suggested the diagnosis which was confirmed by positive staining of Immunoglobulin G4, the dense lympho-plasmacytic infiltrate and elevated serum IgG4 concentrations. A course of steroids followed by mycophenolate mofetil as maintenance immunosuppression rendered the patient afebrile with improvement of renal function.

High prevalence of hyperparathyroidism among peritoneal dialysis patients: a review of 176 patients

OBJECTIVES

Parathyroid dysfunction continues to produce significant morbidity in dialysis patients. Since the introduction of low calcium dialysate for peritoneal dialysis (PD), no large studies have been done to determine the prevalence of parathyroid dysfunction in these patients. This study was done to assess the prevalence of parathyroid disease in the PD population and to determine the risk factors associated with this dysfunction.

DESIGN

We analyzed data on 176 patients who received PD at a single center between August 1998 and February 1999. Clinical data, laboratory variables related to parathyroid function, and data pertaining to dialysis treatment and weekly drug dosing were obtained for each patient on two different occasions, approximately 3 months apart. Variables predictive of the development of parathyroid dysfunction were calculated by univariate and multivariate logistic regression analysis.

RESULTS

Two-thirds of the patients surveyed had an abnormal intact parathyroid hormone (iPTH) level: 47% had an iPTH level more than three times normal, the mean was 54.6+/-35.4 pmol/L; 23% had an iPTH value below the upper limit of normal, here the mean was 3.6+/-1.8 pmol/L. Diabetic patients had lower iPTH levels (22.2+/-28.4 pmol/L) than nondiabetics (33.9+/-34.8 pmol/L) (p = 0.02). On multivariate regression analysis, we found that age, duration of dialysis, Kt/V, serum bicarbonate, and serum ionized calcium levels did not significantly affect parathyroid function. Hyperphosphatemia was the only factor that was associated with the development of secondary hyperparathyroidism in this study population (p = 0.029).

CONCLUSION

There is a high prevalence of hyperparathyroidism in the current PD population. Phosphate control is suboptimal and hyperphosphatemia is an independent risk factor for the development of hyperparathyroidism.

Recurrence of hyperparathyroidism after total parathyroidectomy and autotransplantation in peritoneal dialysis patients

OBJECTIVE

To evaluate the effectiveness of total parathyroidectomy (PTX) with autotransplantation in the treatment of secondary hyperparathyroidism (HPT), and to assess recurrence rate of HPT in this peritoneal dialysis (PD) population.

DESIGN

A retrospective study in a single home PD unit.

PATIENTS

Between 1994 and 1998, 19 of 574 patients on PD underwent PTX for treatment of secondary HPT.

MAIN OUTCOME MEASURES

Clinical and biochemical improvement, recurrence of HPT, improvement in anemia post-PTX.

RESULTS

Nineteen (3.3%) patients required PTX between 1994 and 1998. These 5 men and 14 women ranged in age from 22 to 66 years; they had been on maintenance PD pre-PTX for 47.5 +/- 38.1 months, and were followed for 26.1 +/- 15.5 months post-PTX. Sixteen patients had temporary hypocalcemia that was managed by oral (n = 10) or intravenous (n = 6) calcium supplements and calcitriol, while 3 patients had severe "hungry bone" syndrome postoperatively. One patient had recurrent laryngeal nerve palsy post-PTX. Bone pain disappeared in all 12 patients. Pruritus improved in 12/13 patients; fatigue improved in 15/16 patients. Comparison showed significant differences between hemoglobin and hematocrit values 1 month pre-PTX and 12 months post-PTX (p < 0.05). Parathyroid hormone (PTH) level in 15 (79%) patients returned to normal (< or = 7.6 pmol/L) during the first month post-PTX. In 5/12 (42%) patients, PTH level was < or = 7.6 pmol/L 2 years post-PTX, while in 2/12 (17%), PTH was > 22.8 pmol/L (three times normal) 2 years post-PTX, and 3/5 (60%) patients had a PTH > 22.8 pmol/L 3 years post-PTX.

CONCLUSIONS

Total PTX with autotransplantation is associated with a tendency for recurrence of HPT. Our findings suggest that total PTX with autotransplantation may be an ineffective procedure in controlling HPT over the long term.

Antibody to hepatitis-C virus in multi-transfused thalassaemics--Indian experience

Twelve out of 72 (16.7%) multi-transfused patients with thalassemia major (age range: 7-22 years) were found to be positive for antibody to hepatitis-C virus (anti-HCV). Nine (75%) of these 12 cases were positive for hepatitis B core antibody (anti-HBc) and/or hepatitis B surface antibody (anti-HBs). Out of the remaining 60 patients (83.3%), 27 patients (45%) were positive for anti-HBc and/or anti-HBs, while six (10%) were HBsAg positive Anti-HCV positive patients had significant higher levels of liver enzymes than those who were negative (p < 0.01). S. Ferritin was also significantly higher in those with seropositivity for anti-HCV than those who were negative (p < 0.01). It is concluded that HCV (besides HBV) is a major problem in multi-transfused thalassemia major patients and routine pre-transfusion screening of blood for anti-HCV must be introduced in the blood banks.

Thyroid dysfunction in multi-transfused iron loaded thalassemia patients

Seventy-two transfusion-dependent iron loaded thalassemia patients were investigated for thyroid dysfunction by estimating circulating thyroid hormones (T4 and T3) and basal thyroid stimulating hormone (TSH). They were also evaluated for their liver function (biochemically) and iron overload by estimating serum ferritin. Thyroid failure (hypothyroidism) was documented in 14 patients (19.4%). In all, 3 groups were seen, i.e. Group 1: Normal T4, T3, TSH (58 patients: 80.6%); Group 2: Compensated hypothyroidism characterized by normal T4, T3 and raised TSH (9 patients: 12.5%); Group 3: Decompensated hypothyroidism characterized by decreased T4 and increased TSH (5 patients: 6.9%). Interestingly, impaired thyroid function could not be correlated with age, amount of blood transfused, liver dysfunction or degree of iron overload. It is postulated that an inter-play between chronic hypoxia, liver dysfunction and iron overload may be responsible for the thyroid damage.

Glanzmann's thrombasthenia

During January 1981 to June 1991, 20 patients from 16 unrelated families were detected to have Glanzmann's thrombasthenia (GT). Twelve families (75%) had history of consanguinity, with 6 first cousins and 3 uncle-niece marriages; of these 7 were Muslims, 6 Hindus and 3 Christians. There were 12 girls and 8 boys; the mean age at diagnosis was 7.05 +/- 6.03 yr (range 1 day-22 yr). All cases had initial bleeding prior to the age of 5 yr with the mean age at the initial episode of bleeding being 2.21 +/- 1.34 yr (range 1 day-5 yr). Common pattern of bleeding included epistaxis, gingival bleeding, post-traumatic bruises, menorrhagia, gastrointestinal (2 cases), post-operative (2 cases) and spontaneous bleeding (2 cases). No patient showed hemarthrosis, intracranial bleeding or hemoptysis. Menorrhagia was a serious problem necessitating repeated transfusions and hormonal therapy. Twelve cases (60%) required 1-120 units of blood transfusions while five received platelet concentrates.