1/24. Primary proximal renal tubular acidosis; A therapeutical approach and long term follow-up.This paper reports a case of proximal renal tubular acidosis followed during 4 years, in a 4-year-old girl. High doses of alkali could not be administered owing to gastric intolerance of the patient; diuretic therapy carries the risk of causing severe dehydration or hypotension. We administered such a dose of NaHCO3 to obtain a normal blood pH--with persistent hyperventilation-, subnormal bicarbonatemia, and acid urine. This treatment could cause an improvement of rickets, growth and laboratory data. At present, the biochemical data, including urinary excretion of bicarbonate with normal bicarbonatemia, are normal; this indicates a spontaneous recovery of the syndrome. We think that low doses of alkali are useful in the transient form of proximal renal tubular acidosis to prevent bone lesions and failure to thrive. But even in the irreversible form of this syndrome--when high alkali doses and diuretics cause dangerous effects--this therapy may be useful to treat some symptoms.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
2/24. bone marrow transplantation corrects osteopetrosis in the carbonic anhydrase ii deficiency syndrome.carbonic anhydrase ii (CAII), found in renal tubules, brain, and osteoclasts, is critical in acid-base homeostasis and bone remodeling. Deficiency of CAII gives rise to a syndrome of osteopetrosis, renal tubular acidosis (RTA), and cerebral calcification with associated developmental delay. It is inherited in an autosomal recessive fashion and found most frequently in the mediterranean region and the middle east. We report 2 related Irish families with clinically severe CAII deficiency in whom the gene mutation has been fully elucidated. Two children, one from each family, have undergone allogeneic bone marrow transplantation because of severe progressive visual and hearing loss. The older 2 children had already developed cerebral calcification and marked visual loss at the time of diagnosis and were treated symptomatically. Post-transplantation evaluation at 2 and 3 years demonstrates histologic and radiologic resolution of their osteopetrosis with stabilization of hearing and vision. Both children remain developmentally delayed and continue to have RTA, and the older child has now developed cerebral calcification. Allogeneic bone marrow stem cell replacement cures the osteoclast component of CAII deficiency and retards the development of cerebral calcification, but it appears to have little or no effect on the renal lesions. (blood. 2001;97:1947-1950)- - - - - - - - - - ranking = 3keywords = bone (Clic here for more details about this article) |
3/24. Rapid improvement of osteomalacia by treatment in a case with sjogren's syndrome, rheumatoid arthritis and renal tubular acidosis type 1.We present here a case of sjogren's syndrome (SjS) with osteomalacia based on renal tubular acidosis type 1 (RTA-1). A 53-year-old woman, diagnosed as having rheumatoid arthritis (RA) at the age of 33, was admitted to our hospital because of sicca complex, fatigability and worsening general aching. The activity of RA had been low, but it was complicated by SjS, RTA-1 and remarkable osteomalacia. acidosis was corrected by alkali supplement therapy. By treatment with a regimen consisting of alfacalcidol, calcium L-aspartate, elcatonin and ipriflavone, her bone mineral density (BMD) was remarkably improved within months and the generalized aching gradually diminished.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
4/24. osteopetrosis, renal tubular acidosis without urinary concentration abnormality, cerebral calcification and severe mental retardation in three Turkish brothers.Deficiency of carbonic anhydrase ii (CA II) isoenzyme produces metabolic disorders of bone, kidney and brain. In this report we describe the clinical, radiological, pathological and genetic findings in three brothers who were affected with the autosomal recessive syndrome of osteopetrosis, renal tubular acidosis (RTA) and cerebral calcification. The RTA was hybrid type, but urinary concentration ability was intact. Additional features were severe mental retardation, stunted growth, microcephaly, dental malocclusion, high-arched palate, and broad thumbs. Previous reported patients with this syndrome were predominantly from the middle east and mediterranean region. This is the first report with CA II deficiency from the Turkish population. The presence of mental retardation and relative infrequency of skeletal fractures in our patients resembles the clinical course of patients with the Arabic mutation of the CA II gene, but this mutation was not found in our patients.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
5/24. A phenocopy of CAII deficiency: a novel genetic explanation for inherited infantile osteopetrosis with distal renal tubular acidosis.The rare bone thickening disease osteopetrosis occurs in various forms, one of which is accompanied by renal tubular acidosis (RTA), and is known as Guibaud-Vainsel syndrome or marble brain disease. Clinical manifestations of this autosomal recessive syndrome comprise increased bone density, growth failure, intracerebral calcification, facial dysmorphism, mental retardation, and conductive hearing impairment. The most common cause is carbonic anhydrase ii (CAII) deficiency. Several different loss of function mutations in CA2, the gene encoding CAII, have been described. To date, there have been no exceptions to the finding of CAII deficiency in patients with coexistent osteopetrosis and RTA. Most often, the RTA is of mixed proximal and distal type, but kindreds are reported in which either distal or proximal RTA predominates. We report the molecular genetic investigation of two consanguineous kindreds where osteopetrosis and distal RTA (dRTA) were both manifest. One kindred harbours a novel homozygous frameshift alteration in CA2. In the other, CAII levels were normal despite a similar clinical picture, and we excluded defects in CA2. In this kindred, two separate recessive disorders are penetrant, each affecting a different, tissue specific subunit of the vacuolar proton pump (H( )-ATPase), providing a highly unusual, novel genetic explanation for the coexistence of osteopetrosis and dRTA. The osteopetrosis is the result of a homozygous deletion in TCIRG1, which encodes an osteoclast specific isoform of subunit a of the H( )-ATPase, while the dRTA is associated with a homozygous mutation in ATP6V1B1, encoding the kidney specific B1 subunit of H( )-ATPase. This kindred is exceptional firstly because the coinheritance of two rare recessive disorders has created a phenocopy of CAII deficiency, and secondly because these disorders affect two different subunits of the H( )-ATPase that have opposite effects on bone density, but which have only recently been determined to possess tissue specific isoforms.- - - - - - - - - - ranking = 3keywords = bone (Clic here for more details about this article) |
6/24. Early skeletal effect of alkali therapy upon the osteomalacia of renal tubular acidosis.The administration of alkaline agents to a 16-year-old girl with severe renal tubular acidosis and osteomalacia caused an almost immediate rise of the urinary excretion of total hydroxyproline. The increment of the dyalizable fraction predominated over the nondyalizable component. Gradually serum phosphate and serum alkaline phosphatase increased whereas urinary calcium and magnesium and phosphate clearance declined. serum PTH remained elevated throughout. We suggest that the correction of the metabolic acidosis might increase the transport of phosphate and calcium across the functional bone membrane leading to a rapid deposition of lime salts in the uncalcified matrix with a concomitant increase in bone collagen turnover.- - - - - - - - - - ranking = 2keywords = bone (Clic here for more details about this article) |
7/24. Renal tubular acidosis, Sjogren syndrome, and bone disease.BACKGROUND: There has been disagreement about whether osteomalacia (adult rickets) occurs in adults with type 1 (distal) renal tubular acidosis (RTA1). Therefore, after finding scapular pseudofractures in a patient with RTA1 and Sjogren syndrome, we decided to survey other patients with RTA to learn whether osteomalacia occurred in others and, if it did, whether it was necessarily associated with the presence of Sjogren syndrome. methods: We examined the hospital records and laboratory findings of 250 patients with codes for RTA, 124 with codes for osteomalacia, and 20 with codes for Sjogren syndrome who were seen at a university-affiliated acute care municipal hospital since 1990. Further detailed survey was then limited to patients older than 15 years and excluded those with potentially confounding causes of bone disease such as chronic renal insufficiency or sickle cell disease. Seven adults with RTA1 were thereby identified. RESULTS: Two adults with RTA1 had radiological and biochemical findings compatible with osteomalacia, and 1 had findings compatible with Sjogren syndrome. A third patient without Sjogren syndrome had biochemical findings suggestive of osteomalacia. CONCLUSIONS: osteomalacia seems to occur in some adult patients with RTA1, and not only in association with Sjogren syndrome. We found no biochemical evidence of osteomalacia in the patients with Sjogren syndrome who did not have RTA.- - - - - - - - - - ranking = 1862.7484919368keywords = bone disease, bone (Clic here for more details about this article) |
8/24. Osteal complications as first manifestation in a patient with primary sjogren's syndrome and with associated distal tubular acidosis (type 1) and chronic renal insufficiency.Renal affection is among the complications associated with the sjogren's syndrome. Tubulo-interstitial nephritis constitutes the most frequent renal lesion and distal tubular acidosis (Type 1) is the most important clinical manifestation of this tubular dysfunction, although the occurrence of chronic renal insufficiency is not an uncommon finding in the presence of distal renal tubular acidosis. osteomalacia is a clinical consequence of tubular acidosis caused by buffering of H in the bone. We present the case of a woman with osteal complication a year before being diagnosed with primary sjogren's syndrome and with distal tubular acidosis and renal insufficiency associated at diagnosis.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
9/24. Distal renal tubular acidosis associated with large vestibular aqueduct and sensorineural hearing loss.CONCLUSIONS: hearing loss and equilibrium dysfunction have different etiologies in patients with large vestibular aqueduct syndrome. We suggest that all children with distal renal tubular acidosis (dRTA) should be subjected to an equilibrium study and audiological evaluation, as well as to a CT or MRI scan. OBJECTIVE: dRTA has been described in association with sensorineural hearing loss, but there are no reported cases that have been examined in detail using audiological and equilibrium studies. We report here a case of progressive sensorineural hearing loss with a large vestibular aqueduct and dRTA, and the results of audiological and equilibrium studies. MATERIAL AND methods: A 31-year-old female presented with hearing loss, tinnitus and vertigo. She had been treated with oral sodium citrate, potassium citrate and potassium chloride supplementation because of dRTA since the age of 1 month. RESULTS: The pure-tone audiogram of the patient was off the scale for the right ear and showed progressive sensorineural hearing loss for the left ear. ice-water caloric testing showed canal paresis on the left side. temporal bone CT and inner ear MRI revealed a large vestibular aqueduct and a large endolymphatic sac on both sides.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
10/24. Distal renal tubular acidosis: alkali heals osteomalacia and increases net production of 1,25-dihydroxyvitamin D.In 2 women with distal renal tubular acidosis and osteomalacia, alkali treatment cured the bone disease and was accompanied by marked increases in the serum 1,25 dihydroxyvitamin D concentration, without a significant change in the 25-hydroxyvitamin D concentration.- - - - - - - - - - ranking = 372.54969838737keywords = bone disease, bone (Clic here for more details about this article) |
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