[Management of hyperphosphatemia in patients with chronic kidney disease]

Hyperphosphatemia is a common finding in patients with chronic kidney disease (CKD) undergoing hemodialysis or receiving conservative treatment. Recent papers have reported a link between hyperphosphatemia, soft tissue calcifications, and cardiovascular events responsible for high morbidity and mortality in these patients. Our group identified in salivary phosphate secretion a method to study the phosphate balance in CKD. Moreover, we found that CKD patients on hemodialysis usually drink beverages with a high phosphate content that may increase their serum phosphorus levels. Hyperphosphatemia is currently treated with diet, phosphate-binding drugs, and drugs acting on bone metabolism. Despite such treatment, only half of the patients with end-stage renal disease fall within the K/DOQI guidelines range for serum phosphorus levels. This paper reports positive results obtained with the use of the polymer chitosan as a phosphatebinding chewing gum in CKD patients undergoing periodic hemodialysis.

Cutaneous sterile granulomas/pyogranulomas, leishmaniasis and mycobacterial infections

Cutaneous "sterile" granulomas represent a group of uncommon skin disorders of unknown aetiopathogenesis. Many diseases are included in this group (for example, sterile granuloma/pyogranuloma syndrome and reactive histiocytosis). The definition of sterile is based on the exclusion of other possible aetiological agents (for example, microorganisms or foreign body). Many techniques are used to rule out a microbial aetiology including cytology, histology, immunohistochemistry and culture. However, some organisms are "fastidious" and difficult to culture or to identify with routine methods, and molecular studies are necessary. This is particularly true for mycobacteria (for example, canine leproid granuloma syndrome) and Leishmania. Recently, studies in human and veterinary medicine have proved the presence of microorganisms (mycobacteria and Leishmania) using a polymerase chain reaction technique in specimens previously diagnosed as sterile. Therefore, it is very important, with the development of new technologies, to use a multidisciplinary diagnostic approach to definitively rule out any microorganism before declaring a disease sterile.

[Erectile dysfunction and quality of life in patients with chronic renal failure]

Erectile dysfunction (ED) is associated with a reduced quality of life; it represents a risk factor for the development of depression. ED may induce depression, loss of self-esteem, poor self-image, anxiety, and tension in the relationship with the partner. These emotional disturbances can create physical conditions that lead to increased difficulty in achieving an erection. Depression can deprive a person of the ability to experience many of life's pleasures. It not only affects the mind but also the body--often in unexpected ways. As a result, many men who have been diagnosed with depression find themselves suffering from another condition: ED. Sexual dysfunction is a big problem also in patients with chronic renal failure and seriously affects their quality of life. About 40% of men on dialysis suffer from ED. Many uremic patients have additional symptoms including reduction of libido and a decreased frequency of sexual intercourse. With the start of dialysis some of these symptoms may improve, without, however, returning to normal.

[Nursing and quality of life in CKD]

Quality of life is one of the main targets of modern medicine. This applies specifically to people suffering from chronic diseases, who are frequently hospitalized and receive continuing care for their irreversible condition. Among chronic diseases, end-stage renal disease is extremely interesting because it can be assessed transversely in different settings but also longitudinally over time, thus allowing adequate evaluation of quality of life.

[Health care based on patients' needs]

Survival is not enough. We need to build a health system starting from patients' needs without wasting the resources of our grandchildren and great-grandchildren. We have to switch from curative to preventive medicine by firing managers who think they can resolve all problems by cutting expenditures. We need to educate a new cadre of managers able to govern by centering the system on the patients. Managers should consider health care as an asset and should reinforce clinical research. Such a program has been recently adopted in France.

[Low-protein diet and proteinuria]

Proteinuria has a direct toxic effect on the kidney and is a predictor of renal disease progression and outcome also in nondiabetic patients. Controlling proteinuria by reducing the dietary protein intake slows the progression of renal damage, as has been demonstrated in many experimental and clinical studies with low-protein diets (LPD). Serum albumin increases in LPD-treated kidney patients due to reduced urinary excretion. Moreover, it has been observed that LPD-treated kidney patients can keep an adequate nitrogen balance. Association of LPD with ACE inhibitors or sartans has an antiproteinuric effect stronger than that of LPD or antihypertensives alone, which is due to their different hemodynamic actions in the kidney. ACE inhibitors and sartans can be contraindicated in patients with stage 5 chronic kidney disease, where LPD is the only option for proteinuria control. Conflicting results with soy protein-based diets advise against the use of such diets in patients with nephrotic syndrome.

[Altered calcium-phosphorus metabolism and low-protein diet]

Many metabolic disorders associated with uremia can affect the long-term survival of patients with chronic kidney disease. Such disorders can be defined as: hypocalcemia, increased levels of phosphorus, reduced synthesis of 1,25-dihydroxyvitamin D and serum calcitriol, and reduced expression of vitamin D receptors on parathyroid cells with increased parathyroid hormone levels and secondary hyperparathyroidism. Phosphorus, which plays a crucial role in the progression of progressive renal disease, has been shown to be an independent risk factor for death in hemodialysis patients. Thus, reducing the phosphorus intake by decreasing dietary proteins may slow the progression of renal disease. Hypocalcemia is typically associated with chronic kidney disease. It is due to the reduced intestinal absorption of calcium and the spontaneously reduced protein intake that occur in patients with progressive renal disorders. Activated vitamin D and calcium supplements should be administered to patients who are following low-protein diets to prevent secondary hyperparathyroidism; the doses should be correlated with actual renal function and protein intake.

[Low-protein diet in Italy today: the conclusions of the Working Group from the Italian Society of Nephrology]

The high estimated prevalence of chronic kidney disease (CKD) forcefully supports the need for collaboration among nephrologists, cardiologists, diabetologists and general practitioners, to reduce the cardiovascular risk of CKD patients and delay the start of dialysis. Many studies confirm that reducing the dietary intake of proteins improves uremia as well as acid-base and phosphorus disorders without exposing the CKD patient to the risk of malnutrition. The possibility of delaying renal death and the start of dialysis by almost one to two years is also recognized, thanks in part to the antiproteinuric effect of low-protein diets supplemented with keto acids and essential amino acids. Reducing the dietary protein intake delays the start of dialysis independently of the effect of renin-angiotensin system (RAS)-active antihypertensive drugs. Reduction of the dietary protein intake is indicated in patients with a glomerular filtration rate <25 mL/min (CKD stages 4 and 5). Some situations may, however, require an earlier switch to a low-protein diet, e.g., high proteinuria, renal function worsening at more than 5 mL/min/year, diabetes, and metabolic decompensation. If well designed and properly carried out, reduction of the dietary intake of proteins is not associated with low serum albumin levels or malnutrition, and does not affect patients death. Today, highly palatable, high-quality reduced protein preparations are widely available to reduce the protein intake of CKD patients.

[Low-protein dietary therapy in patients with chronic kidney disease]

Several prospective studies and meta-analyses including the recent Cochrane meta-analysis have demonstrated that reducing the protein content in the diet delays renal death and the start of dialysis in patients with chronic kidney disease (CKD). Reducing the dietary protein intake offers other benefits such as lowering accumulation of uremic toxins and circulating phosphates and improving symptoms and metabolic derangements. Following the publication of the Cochrane meta-analysis, some of the most renowned experts in Italy on dietary therapy in the CKD patient established a working group within the Italian Society of Nephrology (SIN), the ''Nephrontieres'' project. The current supplement of GIN presents the views of the members of the ''Nephrontieres'' group on a range of issues related to dietary therapy in CKD. A CME program for Italian nephrologists also originated from the collaborative work of the group.

Seminal vesicle cysts with unilateral renal agenesis and contralateral ureteral stenosis in a beta-thalassemic patient: an unknown association by incomplete development of the mesonephric duct

We report the case of a 13-year-old male patient with beta-thalassemic trait who presented for a colic pain. An ultrasound of the abdomen revealed absence of the right kidney with a complex hypoechogenic pelvic mass causing mild pressure on the posterior bladder wall. Urography showed hypertrophy of the left kidney with moderate ureteral enlargement of the distal third due to an insertion defect in the bladder suggestive of a primary segmental nonobstructing megaureter. MR studies showed right multilocular seminal vesicle cysts. One year later an MR examination of the pelvis showed an increase in size of seminal vesicle cysts and open surgery was performed to remove the cystic retrovesical mass. Our case represents a very rare association of seminal vesicle cysts, unilateral renal agenesis and alteration in contralateral ureteral insertion in a patient with beta-thalassemic trait.

A new approach to the evaluation of hyperphosphatemia in chronic kidney disease

AIMS

Hyperphosphoremia, main contributor to cardiovascular calcifications, has a major impact on the morbidity and mortality of chronic renal failure (CRF) patients. Phosphate binders and dietary phosphate limitation are not effective enough to abolish hyperphosphoremia-induced cardiovascular abnormalities, therefore, the identification of other and more timely approaches for serum phosphorous reduction is necessary. Salivary fluid contains phosphate which, if related to the daily salivary secretion (1,000 - 1,800 ml), deserves attention as a marker for an earlier start of pharmacologic treatment for phosphorous removal. In ESRD patients under dialysis we have shown increased salivary phosphate closely to be related with serum phosphorous and interpreted as compensatory. This study evaluates salivary phosphate secretion in 77 nondialyzed CRF compared with healthy subjects and its relationship with renal function.

METHODS

Saxon's test confirmed normal salivary function in patients and controls. Serum phosphorous, creatinine and GFR were also measured.

RESULTS

Salivary phosphorous was significantly higher in CRF patients compared with controls: 38.60 mg/dl (range 12.20 - 95.60) vs 16.30 (10.30 - 27.10), p < 0.0001; serum phosphate was also significantly higher: 3.70 (2.10 - 6.80) vs 3.50 (2.3 4.6), p = 0.013. In CRF patients, salivary phosphorous positively correlated with serum phosphorous (r - 0.45, p < 0.0001) and with serum creatinine (r = 0.72, p < 0.0001), while negatively correlated with GFR (r = -0.72, p < 0.0001).

CONCLUSIONS

The results of our study show also in CRF patients increased salivary phosphate secretion, which is related with renal function. On this basis the use of salivary phosphate secretion as a marker for an earlier start of the abnormal phosphate, metabolism pharmacologic treatment could be proposed.

Clinical, biochemical and genetic features of glycogen debranching enzyme deficiency

Deficiency of debrancher enzyme causes Glycogen Storage Disease (GSD) type III, an autosomal recessive disorder, characterized by tissue accumulation of abnormally structured glycogen. This report reviews current clinical and molecular knowledge about this disorder and describes the variability at phenotype and genotype levels of a large group of Italian GSDIII patients.

Investigation on the association between atopic dermatitis and the development of mycosis fungoides in dogs: a retrospective case-control study

In human medicine, the relationship between the immunodysregulation observed in atopic dermatitis (AD) and the development of mycosis fungoides (MF) has triggered considerable interest due to the increasing number of patients with MF who have a previous history of AD. The purpose of this retrospective case-control study was to investigate whether dogs diagnosed with MF were more likely to have AD. The records of 96 000 canine patients at the University of Florida were searched. Inclusion criteria were a clinical and histological diagnosis of MF. Dogs admitted to the University of Florida, Veterinary Medical Center during the same time period (1991-2004) without a diagnosis of MF were included as controls. Four controls for each study dog were randomly selected (matched by year of admission). Frequency of AD and other exposure variables were compared among case and control dogs by using conditional logistic regression. Records of 19 dogs with a diagnosis of MF were identified. Five of them (5/19, 26.3%) had previous diagnosis of AD. The odds of having MF was 12 times (OR = 12.54; 95% CI = 1.95-80.39; P < 0.01) higher in dogs with AD than in dogs without AD. In conclusion, this study suggests an association between AD and MF in dogs. Future studies are necessary to confirm this finding and to investigate the pathogenic mechanisms involved in this association.

Henoch-Schönlein purpura associated with acetaminophen and codeine

We report a case of a relapse of Henoch-Schönlein Purpura (HSP) associated with intake of paracetamol (also known as acetaminophene) and codeine. A 69-year-old man presented with fever, gross hematuria, acute renal failure, palpable purpuric skin rash over the legs, feet and arms, arthralgias and abdominal discomfort. 1 week before he had started therapy with co-efferalgan (association of paracetamol and codeine) for cervical arthrosis. Blood test revealed increase in serum creatinine levels (2.6 mg/dl), CRP (375 mg/dl), with no thrombocytopenia or hypocomplementemia. Co-efferalgan was discontinued. Gross hematuria resolved in 2 days, purpuric rash disappeared in 10 days, renal function returned to normal after 2 weeks and abdominal pain and arthralgias improved on the following 2 - 3 weeks. An objective causality assessment in accordance with the Naranjo algorithm, revealed that the adverse drug reaction was probable between paracetamol/codeine and Henoch-Schönlein purpura. To our knowledge, and based on a medline search (up to 2005), we believe that this could be considered the first case of Henoch-Schönlein purpura, associated with intake of paracetamol and codein. Although this event could be considered rare, clinicians should to be aware of possible associations between HUS and the intake of paracetamol and/or codeine to provide an early therapeutic intervention and a close monitoring.

[Renal replacement therapies in intensive care units: cost analysis]

The medical treatment of intensive care unit patients represents one of the greatest costs in the health care system. Patients affected by acute renal failure account for about -10% of cases: dialysis treatment is of major importance in an economical setting. Recent studies compared continuous renal replacement therapy (CRRT) with intermittent hemodialysis (IHD). Cost comparison of the two methods showed that CRR is more expensive due to the technical device costs, while the intermittent dialysis costs depended mostly on human resources management, e.g. a longer time spent for nurse and hemodyalisis surveillance. Moreover, a higher dialysis dose, easily obtained with CRRT, could improve survival and renal function recovery leading to a reduction in hospitalization and consequently minor health care costs. These parameters, if opportunely evaluated and verified through randomized multicentric trials, could lead to an economical balance between CRRT and IHD; nephrologists, then, could choose a method out of medical and clinical more than economic reasons.

Presence of anti-platelet IgM and IgG antibodies in dogs naturally infected by Leishmania infantum

Thirty-three dogs, naturally infected by Leishmania infantum, were enrolled in the study and were classified as oligo-symptomatic (n. 15) and symptomatic or markedly symptomatic (n. 18). A control group was 10 healthy dogs. A haematological profile was obtained and the dogs serum was employed to assess the presence of platelet binding IgM and IgG antibodies (PBIgM, PBIgG) using flow cytometry. FITC labelled goat anti-dog IgM or IgG were used to detect PBIgM and PBIgG. Samples with a mean fluorescence intensity (MFI) that was 100 channels higher on a log scale for more than 30% of the platelets than seen in negative control platelets from a healthy dog were considered positive for the presence of anti-platelet antibodies (PBIg). Twenty-one (63.3%) dogs revealed the presence of PBIg. Six of them were oligo-symptomatic while 15 showed moderate or severe clinical signs of illness. All the dogs with PBIg showed the presence of PBIgM, with nine animals showing both PBIgM and PBIgG. Nine of 18 symptomatic or markedly symptomatic dogs showed thrombocytopenia, while normal platelet counts were observed in all oligo-symptomatic animals. Eight of 9 thrombocytopenic animals showed the presence of PBIgM, while six of them showed PBIgG. One thrombocytopenic dog was negative for PBIg. This study is the first report documenting the presence of PBIg in natural canine leishmaniasis implying a pathogenic association between thrombocytopenia and the presence of antibody against platelet membrane.

Sevelamer worsens metabolic acidosis in hemodialysis patients

BACKGROUND

Sevelamer hydrochloride, a major phosphate binder for patients on maintenance hemodialysis (MHD) is associated with reduced serum bicarbonate concentration due to hydrochloric acid release in the gut and to the binding of short chain fatty acids in the large intestine. Since metabolic acidosis can be deleterious, a study was devised to compare the time course of serum bicarbonate concentration during treatment with sevelamer hydrochloride or calcium carbonate.

METHODS

Sixteen well nourished patients on MHD who were in excellent clinical conditions and achieving target levels for blood pressure (BP) and hemoglobin (Hb), while on a protein intake of 1.1g/kg body weight (bw), were enrolled in the study. After a 2-week washout period, the patients were divided into two groups, each consisting of eight patients, and randomized either to 24 weeks of sevelamer followed by 24 weeks of calcium carbonate (group A) or to 24 weeks of calcium carbonate followed by 24 weeks of sevelamer (group B). Protein intake, n-protein catabolic rate (nPCR), serum concentrations of calcium, phosphate, calcium x phosphate (Ca x P) product, bicarbonate, intact parathyroid hormone (iPTH) and albumin were monitored. Time course changes in serum bicarbonate concentrations in relation to short and long dialytic intervals (48 vs. 72 hr) were also investigated.

RESULTS

Both sevelamer and calcium carbonate effectively controlled serum phosphate and the Ca x P product. During calcium carbonate treatment plasma phosphate concentrations were significantly below those of patients on sevelamer. Plasma bicarbonate concentration fell within target DOQI values during calcium carbonate administration both in group A and in group B, a goal which was not achieved under sevelamer administration. After a long dialytic interval in patients on sevelamer, serum bicarbonate concentration averaged 17.3 +/- 1.1 mEq/L, whereas it averaged 21.1 +/- 0.7 mEq/L in patients on calcium carbonate (p<0.01). Finally, a 24-week sevelamer administration caused a statistically significant (p<0.05) reduction (0.8 g/dL) in serum albumin concentration, without affecting iPTH. Taken together, these results indicate that sevelamer worsens metabolic acidosis, which needs to be corrected.