Phosphate binder

Hollow Fiber with Sorbent Walls. A cellulose sorbent and dialy2ing membrane hoUow fiber was reported in 1977 by Enka Glan2stoff AG (41). This hoUow fiber, with an inside diameter of about 300 p.m, has a double-layer waU. The inner waU consists of Cuprophan ceUulose and is very thin, approximately 8 p.m. The outer waU, which is ca 40-p.m thick, consists mainly of sorbent substance bonded by ceUulose. The advantage of such a fiber is that it combines the principles of hemodialysis with those of hemoperfusion. Two such fibers have been made one with activated carbon in the fiber waU, and one with aluminum oxide, which is a phosphate binder (also see Dialysis). 

Advanced stages Increased potassium, phosphorus, and magnesium decreased bicarbonate (metabolic acidosis) calcium levels are generally low in earlier stages of CKD and may be elevated in stage 5 CKD, secondary to the use of calcium-containing phosphate binders. 

Hyperphosphatemia is generally benign and rarely needs aggressive therapy. Dietary restriction of phosphate and protein is effective for most minor elevations. Phosphate binders such as aluminum-based antacids, calcium carbonate, calcium acetate (PhosLo , Nabi), sevelamer (Renagel , Genzyme), and lanthanum carbonate (Fosrenol , Shire) may be necessary for some patients.43 If patients exhibit findings of hypocalcemia (tetany), IV calcium should be administered empirically. 

In the beginning of the eighties, the clinical application of DFO expanded to a new type of patient, namely those on maintenance dialysis. As we will see in Chapter 12, some patients suffered from aluminium overload, mostly due to the use of aluminium salts as phosphate binders, while others had obvious transfusional iron overload in the pre-erythropoietin era. DFO was therefore used either to remove aluminium, excess iron or both. Nephrologists established that DFO therapy did not increase the overall incidence of bacterial infections but that it slightly increased the risk of bacteraemia caused by Y. enterocolitica or Y. pseudotuberculosis, as had been previously observed in thalassaemic patients (Boelaert et ah, 1987 Tielemans et ah,... 

Hergesell, O. Ritz, E., Phosphate binders on iron basis a new perspective Kidney Int. Suppl. 1999, 73, S42-45. 

Adverse effects of calcium-containing phosphate binders, as well as sevel-amer and lanthanum, include constipation, diarrhea, nausea, vomiting, and abdominal pain. The risk of hypercalcemia is also a concern. To avoid potential drug interactions, phosphate binders should be administered 1 hour before or 3 hours after other oral medications. 

The most effective way to treat hyperphosphatemia is to decrease phosphate absorption from the GI tract with phosphate binders (see Chap. 76, Table 76-3). 

Loghman-Adham, M. (1999) Phosphate binders for control of phosphate retention in chronic renal failure. Pediatr. Nephrol. 13 701-708 Lorenz, M. Kempe, G. (1987) Substitution des Eisen(III) im p-FeOOH. Wiss. Zeitschr. 

Lanthanum Carbonate (Fesrenol) [Renal GU Agent/ Phosphate Binder] Uses Hyperphosphatemia in renal Dz Action Phosphate binder Dose 750-1500 mg PO daily -5- doses, w/ or immediately after meal titrate q2-3wk based on P04 levels Caution [C, /-] No data in GI Dz Disp Chew tabs SE NA, graft occlusion, HA, BP EMS N/V is common, monitor for hypovolemia and electrolyte disturbances OD May cause extension of nl SEs symptomatic and supportive... 

Series of various mono,- bi-, and poly-(thio)urea-functionalized (poly)saccha-rides have already been synthesized and studied for molecular recognition of, e.g., dimethyl and phenylphosphate as model compounds for monoanionic and polyanionic phosphate esters, respechvely [111]. Thiourea derivatives such as 195-197 were analyhcally identified to provide double hydrogen bonding mediated host-guest complexes of well-defined dimension and orientations and were also reported to serve as phosphate binders even in the hydrogen bonding environment of water (Figure 6.57) [111]. 

Can be used alone or in combination with vitamin D sterols and/or phosphate binders... 

Progressive encephalopathy was also observed among children with severe renal disease ingesting aluminum-containing phosphate binders (Finberg et al. 1986 Griswold et al. 1983). 

Andrcoli SP, Bergstein JM, Sherrard DJ. 1984. Aluminum intoxication from aluminum-containing phosphate binders in children with azotemia not undergoing dialysis. N Engl J Med 310 1079-1084. 

Chan JCM, Jacob M, Brown S, et al. 1998. Aluminum metabolism in rats Effects of vitamin-D, dihydrotachysterol, 1,25-dihydroxyvitannn-D and phosphate binders. Nephron 48 61-64. 

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