{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T12:18:29Z","timestamp":1792153109226,"version":"4.4.0"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2009,9,30]],"date-time":"2009-09-30T00:00:00Z","timestamp":1254268800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2009,9,30]],"date-time":"2009-09-30T00:00:00Z","timestamp":1254268800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biol Neonate"],"abstract":"<jats:p>To determine the effect of a short course of methylxanthines on renal function and on urinary calcium excretion, 20 premature neonates affected by apnea or moderate respiratory distress syndrome were randomly assigned to either a theophylline treatment or to a caffeine treatment group. The protocol included a 24-hour pretreatment study period (I) and a subsequent 24-hour period (II) following 5 days of theophylline (loading dose 5 mg\/kg i.v., maintenance dose 2.5 mg\/kg\/l2 h) or caffeine (loading dose 10 mg\/kg i.v., maintenance dose 2.5 mg\/kg\/l2 h) administration. Pre- and postxanthine treatment serum sodium, potassium, calcium and phosphorus remained stable, while serum creatinine decreased significantly (p &lt; 0.05). Furthermore, from period I to period II, sodium urine excretion, fractional Na excretion and creatinine clearance remained statistically comparable in both study groups, along with a significant increase (p &lt; 0.05) in calciuria, urinary Ca\/creatinine and urinary Ca\/Na. Predose caffeine and theophylline serum levels, assessed on the 5th day of treatment, were 12.8 \u00b1 1.8 and 7.9 \u00b1 1.7 \u03bcg\/ml, respectively. Compared to control healthy untreated prematures, the studied premature infants showed a statistically significant increase in urine calcium excretion (10- to 15-fold), which was more evident in the theophylline group. Our data suggest further investigation to determine the long-term renal effects of methylxanthines in premature neonates, to improve assessment of the risk of nephrocalcinosis and osteopenia, in particular in association with various diuretic therapies.<\/jats:p>","DOI":"10.1159\/000244234","type":"journal-article","created":{"date-parts":[[2009,10,2]],"date-time":"2009-10-02T05:47:33Z","timestamp":1254462453000},"page":"169-174","source":"Crossref","is-referenced-by-count":55,"title":["Methylxanthines Increase Renal Calcium Excretion in Preterm Infants"],"prefix":"10.1159","author":[{"given":"Vincenzo","family":"Zanardo","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Dani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniele","family":"Trevisanuto","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Meneghetti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Guglielmi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Graziella","family":"Zacchello","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Felice","family":"Cantarutti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"127","published-online":{"date-parts":[[2009,9,30]]},"container-title":["Biology of the Neonate"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/244234","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000244234","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T22:31:08Z","timestamp":1777674668000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000244234"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,9,30]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000244234","archive":["Portico"],"relation":{},"ISSN":["0006-3126","1421-9727"],"issn-type":[{"value":"0006-3126","type":"print"},{"value":"1421-9727","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,9,30]]}}}