Broncholithiasis is a rare but distinct and potentially dangerous pulmonary problem that still needs to be considered in the differential diagnosis of some patients with bronchial obstruction. Broncholiths originate from calcified material in peribronchial lymph nodes eroding into the tracheobronchial tree. The clinical and chest X-ray signs are usually non-specific, but the diagnosis can nowadays be made based on clinical suspicion, CT-scan and fibre-optic bronchoscopy findings, so that a malignant cause of airway obstruction can be ruled out. The removal of broncholiths during fibre-optic bronchoscopy is seldom possible and rather dangerous. They can be removed safely by rigid bronchoscopy with the aid of Nd-YAG laser photocoagulation. Thoracotomy is indicated in complicated cases with fistula formation or severe bleeding. (+info)
Biophysical characterization of lithostathine. Evidences for a polymeric structure at physiological pH and a proteolysis mechanism leading to the formation of fibrils.
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Lithostathine is a calcium carbonate crystal habit modifier. It is found precipitated under the form of fibrils in chronic calcifying pancreatitis or Alzheimer's disease. In order to gain better insight into the nature and the formation of fibrils, we have expressed and purified recombinant lithostathine. Analytical ultracentrifugation and quasi-elastic light scattering techniques were used to demonstrate that lithostathine remains essentially monomeric at acidic pH while it aggregates at physiological pH. Analysis of these aggregates by electron microscopy showed an apparently unorganized structure of numerous monomers which tend to precipitate forming regular unbranched fibrils. Aggregated forms seem to occur prior to the apparition of fibrils. In addition, we have demonstrated that these fibrils resulted from a proteolysis mechanism due to a specific cleavage of the Arg(11)-Ile(12) peptide bond. It is deduced that the NH(2)-terminal undecapeptide of lithostathine normally impedes fiber formation but not aggregation. A theoretical model explaining the formation of amyloid plaques in neurodegenerative diseases or stones in lithiasis starting from lithostathine is described. Therefore we propose that lithostathine, whose major function is unknown, defines a new class of molecules which is activated by proteolysis and is not involved in cytoskeleton nor intermediate filament functions. (+info)
Study of urinary acidification in patients with idiopathic hypocitraturia.
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Hypocitraturia (HCit) is one of the most remarkable features of renal tubular acidosis, but an acidification defect is not seen in the majority of hypocitraturic patients, whose disease is denoted idiopathic hypocitraturia. In order to assess the integrity of urinary acidification mechanisms in hypocitraturic idiopathic calcium stone formers, we studied two groups of patients, hypocitraturic (HCit, N = 21, 39.5 +/- 11.5 years, 11 females and 10 males) and normocitraturic (NCit, N = 23, 40.2 +/- 11.7 years, 16 females and 7 males) subjects, during a short ammonium chloride loading test lasting 8 h. During the baseline period HCit patients showed significantly higher levels of titratable acid (TA). After the administration of ammonium chloride, mean urinary pH (3rd to 8th hour) and TA and ammonium excretion did not differ significantly between groups. Conversely, during the first hour mean urinary pH was lower and TA and ammonium excretion was higher in HCit. The enhanced TA excretion by HCit during the baseline period and during the first hour suggests that the phosphate buffer mechanism is activated. The earlier response in ammonium excretion by HCit further supports other evidence that acidification mechanisms react promptly. The present results suggest that in the course of lithiasic disease, hypocitraturia coexists with subtle changes in the excretion of hydrogen ions in basal situations. (+info)
Pulmonary alveolar lithiasis in two siblings.
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Pulmonary alveolar microlithiasis (PAM) is a rare disease of unknown etiology and is characterized by the deposition of calcium phosphate microliths within the alveolar airspaces. We report 2 asymptomatic siblings, a 7-year-old girl and her 13-year-old brother, with PAM. In the girl, chest X-ray and computed tomography revealed diffuse interstitial changes but no uptake of technetium 99m (99mTc) on bone scan was noted in the lung. Microliths stained pink with Papanicolaou dye in bronchoalveolar lavage fluid (BALF) but did not stain with von Kossa. In the brother, characteristic radiological findings and 99mTc uptake in the lung were detected. The microliths stained pink with Papanicolaou in BALF and black with von Kossa as well. We hypothesize that the first case is in the early phase of PAM because of lack of 99mTc uptake. (+info)
Effects of testicular microlithiasis on Doppler parameters: report of three cases.
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BACKGROUND: Testicular microlithiasis is a rare, usually asymptomatic, non-progressive disease of the testes associated with various genetic anomalies, infertility and testicular tumors. According to our literature search, there is no specific data about Doppler findings in this disease. CASE PRESENTATION: Doppler findings of three cases of testicular microlithiasis during last two years in our institution are presented. CONCLUSIONS: Although our hypothesis was to find increased Doppler parameters due to intratesticular arterial compression, our findings suggest that there are no Doppler findings specific to testicular microlithiasis. (+info)
Down stream involvement of the bile duct in hepatolithiasis.
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OBJECTIVE: To evaluate the down stream involvement of the bile duct in hepatolithiasis. METHODS: Mechanical damage to bile duct epithelia and long standing cholangitis as result of hepatolithiasis play an important role in the carcinogenesis of bile duct epithelia and stricture of the intra- and extra-hepatic bile duct. Macromorphological and microscopic changes in bile duct mucosa of 100 consecutive patients with hepatolithiasis were investigated using intra- or post-operative cholangioscopy. Biopsy specimens of lesions obtained during cholangioscopy were studied with immunohistochemical staining and flow cytometry to determine proliferative activity and DNA content. Five cases of well-proven cholangiocarcinoma were simultaneously studied as controls. RESULTS: Of the 100 patients, those with chronic cholangitis accounted for 86% (86/100), proliferative lesions 11% (11/100), adenomatous polyps 1% (1/100), and adenocarcinoma 2% (2/100). The obvious mucosal lesion associated with hepatolithiasis was located down-stream of the bile duct, predominantly in the hilar region, e.g. orifices of the right/left hepatic duct and common hepatic duct (73% mucosa lesions in the hilar region). The intensity of cancer embryonic antigen stain and the proliferative cell nuclear antigen index increased with the development of bile duct lesions. Aneuploid DNA presented mainly in the high degree malignant adenocarcinomas (> 80% of cases). CONCLUSIONS: The obvious mucosal lesions associated with hepatolithiasis were located down-stream of the bile duct, predominantly in the hilar region (73% of mucosal lesions). The proliferative activity of examined bile duct mucosa lesions increased with the development of pathological deterioration, which may contribute to the development of hilar bile duct stricture and hilar cholangiocarcinoma. (+info)
A variant of pulmonary alveolar microlithiasis in nackt mice.
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Four adult mutant nackt mice, which demonstrate alopecia and CD4+ T-cell deficiency, and two outbred SENCAR mice (sentinels) were presented for routine health surveillance. Lesions were not observed at necropsy. Microscopically, all four nackt mice demonstrated multiple concretions that were 30-100 microm in diameter, irregularly rounded to oval, nonbirefringent, and amphophilic to basophilic. Many of the concretions appeared attached to or within the alveolar walls of all lung lobes. Approximately half of the concretions had irregular fracture lines. All concretions were periodic acid-Schiff positive, and Von Kassa staining revealed diffuse calcification. None of the concretions were associated with inflammatory cell infiltrates, and metaplastic ossification was not evident. A diagnosis of pulmonary alveolar microlithiasis, a rare disease in both humans and animals, was made based on the size and location of the concretions and the lack of an inflammatory response. This is the first report of a laboratory mouse demonstrating pulmonary alveolar microlithiasis. (+info)
Broncholithiasis and lithoptysis associated with silicosis.
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A case of broncholithiasis associated with massive silicosis is reported, showing a rare aspect of parenchymal lesions generating broncholiths as well as the presence of recurrent lithoptysis, with subsequent regression of radiological lesions. Aetiological, clinical, physiopathological, and radiological aspects of the disease are discussed, demonstrating the importance of the use of computed tomography in diagnosis. The mineralogical analysis of expectorated fragments is also shown. (+info)