Vitamin D reduces renal NaPi-2 in PTH-infused rats: complexity of vitamin D action on renal P(i) handling.

Acute administration of dihydroxycholecalciferol [1,25(OH)(2)D(3)] blunts phosphaturia and increases urinary cAMP excretion in parathyroid hormone (PTH)-infused parathyroidectomized (PTX) rats. Because chronic administration of 1,25(OH)(2)D(3) enhances the phosphaturic response to exogenous parathyroid hormone despite blunting of urinary cAMP excretion, we have examined the expression of the renal cortex type II Na-P(i) cotransporter (NaPi-2) mRNA and protein in 1) chronic PTX Sabra rats, 2) PTX rats receiving a physiological dose of 1,25(OH)-2-D(3), 3) PTX rats receiving 35 ng/h of PTH, and 4) rats receiving both PTH and 1,25(OH)(2)D(3), for 7 days via osmotic minipumps. Our results confirm that there is increased phosphaturia in the PTH+1,25(OH)(2)D(3)-infused animals despite blunting of urinary cAMP excretion, a reduced filtered load of phosphate, and lack of a phosphaturic effect by 1,25(OH)(2)D(3) alone. Both PTH and 1,25(OH)(2)D(3) significantly reduced expression of renal cortex NaPi-2 mRNA and NaPi-2 protein, and the administration of PTH together with 1,25(OH)(2)D(3) had additive effects in further decreasing NaPi-2 mRNA and NaPi-2 protein levels. Expression of two other epithelial transporters, type 1 Na-sulfate and type 1 Na-glucose cotransporters, were not different between the groups, suggesting specificity of the effects of PTH and 1,25(OH)(2)D(3) on phosphate transport. The effect of chronic administration of 1,25(OH)(2)D(3) has not been noted previously, and the cellular mechanisms and signaling processes that mediate the decrease in NaPi-2 remain to be determined.

Detection of human herpesvirus-8 DNA in kidney allografts prior to the development of Kaposi's sarcoma.

Human herpesvirus-8 (HHV-8) DNA was identified in kidney allografts in 2 of 3 transplant recipients prior to the development of Kaposi's sarcoma, and increase in viral antibody titer was found in the third. Combined genotypic and serologic analyses could be used to identify patients at risk and suggest that the kidney may be a site of HHV-8 latency.

Overview of ocular allergy treatment.

A plethora of drugs is available for the treatment of ocular allergy. Traditional treatment includes antihistamine and antihistamine/vasoconstrictor combination eyedrops. These drugs are useful, safe, and readily available. Mast cell stabilizers are safe, effective, and an important component of antiallergic therapy. Nonsteroidal anti-inflammatory drugs also have antiallergic effects. In recent years, drugs with multiple mechanisms of action have proven to be effective antiallergics. These drugs often have mast cell stabilizing, antihistaminic, and anti-inflammatory properties. Corticosteroids are considered to be more potent than other antiallergic drugs, and modifications in their molecular structures have made certain corticosteroids suitable for the treatment of ocular allergy.

Evaluation of the onset and duration of effect of azelastine eye drops (0.05%) versus placebo in patients with allergic conjunctivitis using an allergen challenge model.

OBJECTIVE: The trial evaluated the effectiveness of the investigational antihistaminic and antiallergic compound Azelastine Eye Drops (AZE) in the treatment of allergic conjunctivitis using an allergen challenge model. DESIGN: Randomized, double-blind, placebo-controlled, paired-eye study. PARTICIPANTS: Adults with a history of allergic conjunctivitis (>/=2 years) who were asymptomatic throughout the trial, had a positive skin test (cat dander, grass, or ragweed pollen within the last year), and had a positive conjunctival reaction (score 2+ or more for itching and redness in both eyes on a 0-4 scale) during two separate conjunctival provocation tests (CPT) before randomization. METHODS: Eighty patients underwent a 2-week screening period (visits 1 and 2) that included a CPT during visit 1 to establish the allergen threshold dose and a second confirmatory CPT performed at visit 2. Eye symptom assessments for itching (evaluated by patient) and conjunctival redness (evaluated by physician) were performed 5 and 10 minutes after CPT using a 5-point scale (from 0 = none to 4+ = severe). Qualified patients were randomized to receive one drop of AZE (0.015 mg of azelastine hydrochloride) in one eye and one drop of placebo in the other eye 20 minutes before CPT at visit 3 (onset) and 8 or 10 hours before CPT at visit 4 (duration). MAIN OUTCOME MEASURES: Individual severity scores for itching (evaluated by patient) and conjunctival redness (evaluated by physician) for each eye at 3, 5, and 10 minutes after CPT at visits 3 and 4 using a 5-point scale (0 = none to 4+ = very severe). RESULTS: Each of the 80 randomized patients completed the trial. Mean itching and conjunctival redness scores at visit 3 (onset) were significantly lower (P: < 0.001) in the AZE-treated eyes than in the placebo-treated eyes. At visit 4 (duration), mean itching and conjunctival redness scores (P:

Response to growth hormone therapy in experimental ischemic acute renal failure.

In acute renal failure (ARF), the gene and peptide expression of insulin-like growth factor-I (IGF-I) falls. Because IGF-I is regulated by growth hormone (GH) and because kidney GH receptor expression is also attenuated in ARF, the impaired IGF-I expression may partly reflect local GH resistance. Because IGF-I treatment accelerates recovery from ARF, we determined whether high-dose GH therapy could overcome this putative GH resistance, stimulate IGF-I production, and enhance recovery. Rats with ARF were given 2.5 mg GH or vehicle (V) over 2 days, beginning 24 hours before the onset of ARF. GH prevented weight loss but did not modify the course of ARF. Next we determined whether the failure of GH to modify kidney recovery could reflect a failure to stimulate renal IGF-I gene expression. Rats were treated with GH or V over an 18-hour period beginning 1 day after the induction of ARF. Hepatic IGF-I mRNA and serum IGF-I peptide levels rose significantly with GH treatment, but the low kidney IGF-I mRNA levels did not respond. We conclude that the failure of GH to enhance recovery from ARF is caused by impaired GH-stimulated renal IGF-I production, while the maintenance of body weight likely reflects the systemic effects of the increase in hepatic IGF-I production.

The insulin-like growth factor-I axis in acute renal failure.

We have examined the response of the renal insulin-like growth factor (IGF-I) axis to acute ischemic injury in the rat Key findings included a decrease in IGF-I mRNA and peptide levels, a decrease in GH receptor gene plus protein expression and a decrease in the IGF binding proteins except for IGF binding protein I. Administration of GH to compensate for the reduced GH receptor binding corrected the IGF-I mRNA levels suggesting a relative GH deficiency. Interestingly, IGF-I receptor mRNA levels were unchanged while plasma membrane IGF-I receptor number increased two fold. This appeared to be due to a redistribution of receptors to a membrane location. IGF-I receptor autophosphorylation and tyrosine kinase activity were intact despite severe uremia for up to 6 days. We propose that this increase of functional IGF-I receptors following acute tubular necrosis will sensitize the kidney to the administration of exogenous IGF-I.

Insulin-like growth factor-I treatment to enhance renal function in advanced chronic renal failure.

Because of the potential for IGF-I to enhance renal function in advanced chronic renal failure (CRF) we set out to determine whether IGF-I can induce a sustained increase in renal function in patients with near end-stage renal failure. To this end we first examined the impact of CRF on the pharmacokinetics of IGF-I and then we examined the effect of prolonged IGF-I treatment on the renal function of patients with an average GFR of 17 mL/min/1.73 m2. Interestingly the metabolic clearance rate of IGF-I in CRF subjects was similar to that in normal subjects even though the total serum IGF-I levels rose to higher maximum levels. This increase was due to a reduced volume of IGF-I distribution, a consequence of the elevated serum IGF binding proteins in CRF subjects. Treatment with IGF-I (60 mg/kg twice daily sc) for 31 days resulted in a 14% and 18% increase in the inulin and PAH clearances respectively (n = 6 patients). These parameters returned to basal levels on stopping treatment. Serum immunoreactive IGFBP-3 levels fell and IGFBP-2 and -3 levels rose during IGF-I therapy. Adverse effects were mild, of short duration and easily manageable. Thus IGF-I pharmacokinetics are largely unchanged in CRF and the administration of IGF-I produces a modest improvement in the GFR. These results appear to justify more extensive examination of the therapeutic role of IGF-I in the treatment of CRF.

End-stage renal interstitial fibrosis in an adult ten years after ifosfamide therapy.

A 33-year-old male presented with end-stage renal failure. Renal biopsy showed severe interstitial fibrosis without glomerulopathy or vasculopathy. More than 10 years previously the patient had been successfully treated for recurrent rhabdomyosarcoma. The treatment included ifosfamide, a drug known to cause acute tubular dysfunction. Though a possible synergistic effect of previous radiation which was well within accepted tolerance limits cannot be excluded, it would appear that ifosfamide was almost certainly the major cause of the late onset chronic renal disease.

Twice-a-day versus four-times-a-day ofloxacin treatment of external ocular infection.

PURPOSE: The purpose of this study was to compare the efficacies of 0.3% ofloxacin eyedrops, when given twice-a-day (BID) versus four-times-a-day (QID), for the treatment of external ocular disease. METHOD: Fifty patients with blepharitis, conjuctivitis, or blepharoconjunctivitis were randomly assigned to treatment with 0.3% ofloxacin eyedrops, BID or QID, for 10 days. Signs, symptoms, and cultures were evaluated at the beginning and at the end of the study. RESULTS: The clinical outcome was virtually identical in the two groups. There was a significant decrease in clinical scores in the BID and QID groups by days 3 to 5 (2.6-3.0 points) and a further decrease by day 11 (4.3-5.0 points). There was no significant difference between the two groups at any time interval. Microbiologic studies showed a reduction in colony-forming units in 87% of the BID group and in 80% of the QID group. CONCLUSION: The treatment of external ocular disease with 0.3% ofloxacin eyedrops was equally effective when given BID or QID.

The current and future therapy of allergic conjunctivitis.

A wealth of antiallergic drugs is available for ocular allergy, and many new drugs will soon be approved. Pharmaceutical companies frequently seek approval of anti-inflammatory drugs for allergic indications, because it is relatively easy to perform clinical trials for ocular allergy. Extremely safe drugs for mild to moderate degrees of allergic conjunctivitis include antihistamines, mast cell stabilizers, and nonsteroidal anti-inflammatory agents. Topical corticosteroids, preferably those with reduced side effects, are available for more severe forms of ocular allergy. The choice of an antiallergic drug may be guided by the indication for which the drug was approved. The ultimate selection will be made based on the patient's symptoms, the drug's availability, and its cost.

Renal failure, paraproteinemia, and lung squamous cell carcinoma.

A 66-year-old man presented with gastrointestinal symptoms and acute renal failure. He had paraproteinemia and tested positive for antinuclear antibodies. There was no evidence for autoimmune disorder or amyloidosis, and bone marrow biopsy was not consistent with multiple myeloma. Three months later he presented with diffuse lymphadenopathy and right lung mass, and lymph node histology revealed metastatic squamous cell carcinoma. This association of paraproteinemia and nonlymphatic neoplasia is unusual and still very rare. A review of the literature is presented.

A double-masked, placebo-controlled evaluation of the efficacy and safety of loteprednol etabonate in the treatment of giant papillary conjunctivitis. The Loteprednol Etabonate Giant Papillary Conjunctivitis Study Group I.

PURPOSE: To evaluate the safety and effectiveness of loteprednol etabonate 0.5% ophthalmic suspension in reducing the ocular signs and symptoms accompanying contact lens-associated giant papillary conjunctivitis. METHODS: In a randomized, double-masked, placebo-controlled, parallel-group study conducted at 14 academic or private practice clinics, 223 adults with contact lens-associated giant papillary conjunctivitis received either loteprednol or the loteprednol vehicle (placebo), one drop, four times daily for 6 weeks. Papillae, itching, contact lens intolerance, other signs and symptoms of giant papillary conjunctivitis (O-to-3 or O-to-4 grade scales), and intraocular pressure were measured. RESULTS: The proportion of patients treated with loteprednol who at final visit demonstrated an improvement in papillae of at least one grade (78%, 85/109) was significantly greater than the proportion of those treated with placebo (51%, 56/110; P = .001). A treatment difference favoring loteprednol was seen with improvement in itching (95% vs 81%, 104/109 vs 89/110; P < .001) and lens intolerance (87% vs 77%, 95/109 vs 85/110; P = .053). Eight of 109 patients (7%, all taking loteprednol) had an intraocular pressure increase of 10 mm Hg or more on at least one visit during treatment. After discontinuation of loteprednol, intraocular pressure returned to normal levels. Both treatments were well tolerated, and no serious unexpected treatment-related medical events were reported. CONCLUSIONS: The rapid therapeutic response combined with the low incidence and transient nature of any intraocular pressure increase suggests that loteprednol is an appropriate treatment for giant papillary conjunctivitis.

Clustering of Pneumocystis carinii pneumonia in patients undergoing renal transplantation from living unrelated donors in Iraq and India.

Over the past few years, we have observed a substantial increase in the number of patients followed at our hospital who have undergone renal transplantation from living unrelated donors (LURD). These transplants were all performed in one of two centers: Bagdad, Iraq or Bombay, India. We have observed a parallel increase in the number of cases of Pneumocystis carinii pneumonia (PCP) post-renal transplant. We conducted a ten-year retrospective analysis (1986-1995) of patients who developed PCP post-renal transplant to determine the risk factors associated with the development of this infection, with particular reference to the type of transplant and the center in which the transplant was performed. Over this period, 270 renal transplant patients were followed at this hospital and 10 episodes of PCP were documented (3.7%). Six of these cases occurred within the last 2 years, as compared to only 4 cases in the preceding 8 years. All of the cases observed in the last 2 years occurred in patients who had undergone renal transplantation from LURD in Iraq or in India. During the same period, we observed no cases of PCP in patients who had undergone transplantation in Israel (cadaver or related living donor transplants). We could find no difference between patients undergoing transplant from LURD and those undergoing other transplants in terms of immuno-suppressive therapy, frequency of organ rejection episodes or coexistent CMV infection. All patients were of Arab descent and live in the West Bank. Although we cannot identify any obvious explanation for this association, we believe that these cases represent a true cluster phenomenon. We therefore feel it is warranted for all recipients of renal transplants from living unrelated donors seen in our hospital to receive prophylactic therapy for Pneumocystis carinii pneumonia.