Oral metagenomes from Native American Ancestors reveal distinct microbial lineages in the pre-contact era.

OBJECTIVES: Limited studies have focused on how European contact and colonialism impacted Native American oral microbiomes, specifically, the diversity of commensal or opportunistically pathogenic oral microbes, which may be associated with oral diseases. Here, we studied the oral microbiomes of pre-contact Wichita Ancestors, in partnership with the Descendant community, The Wichita and Affiliated Tribes, Oklahoma, USA. MATERIALS AND METHODS: Skeletal remains of 28 Wichita Ancestors from 20 archeological sites (dating approximately to 1250-1450 CE) were paleopathologically assessed for presence of dental calculus and oral disease. DNA was extracted from calculus, and partial uracil deglycosylase-treated double-stranded DNA libraries were shotgun-sequenced using Illumina technology. DNA preservation was assessed, the microbial community was taxonomically profiled, and phylogenomic analyzes were conducted. RESULTS: Paleopathological analysis revealed signs of oral diseases such as caries and periodontitis. Calculus samples from 26 Ancestors yielded oral microbiomes with minimal extraneous contamination. Anaerolineaceae bacterium oral taxon 439 was found to be the most abundant bacterial species. Several Ancestors showed high abundance of bacteria typically associated with periodontitis such as Tannerella forsythia and Treponema denticola. Phylogenomic analyzes of Anaerolineaceae bacterium oral taxon 439 and T. forsythia revealed biogeographic structuring; strains present in the Wichita Ancestors clustered with strains from other pre-contact Native Americans and were distinct from European and/or post-contact American strains. DISCUSSION: We present the largest oral metagenome dataset from a pre-contact Native American population and demonstrate the presence of distinct lineages of oral microbes specific to the pre-contact Americas.

[Research on the relationship between V444A mutation of ABCB11 gene and primary intrahepatic stone].

Objective: To investigate the relationship between V444A mutation of the ABCB11 gene and primary intrahepatic stone (PIS). Methods: A total of 164 patients (including 91 males and 73 females, with an average age of (46.0±13.0) years) with PIS and 164 healthy (including 99 males and 65 females, with an average age of (43.8±16.7) years) volunteers were enrolled in this case-control study between October 2017 and June 2019. TaqMan-MGB was used for detecting the V444A polymorphism site of the ABCB11 gene. All the genotypes and allele frequencies were calculated. Pearson chi-squared test was performed to detect the differences in allele and genotype distribution between the two groups. Logistic regression analysis was used to identify genotypes associated with PIS. Results: There was no significant difference in age and gender between the two groups(both P>0.05). The distributions of V444A allele and genotype accorded with Hardy-Weinberg equilibrium law (P=0.161), which indicated that the selected control group represented statistically acceptable sample. Two alleles of T and C, and three genotypes of TT, TC and CC were detected in the locus of V444A. The T and C allele frequencies in the PIS group and the control group were 28.4% vs 35.4%, and 71.6% vs 64.6%, respectively. The frequencies of the T and C alleles were not different between the two groups (P=0.054). The frequencies of TT, TC and CC genotypes in the two groups were 5.5%, 45.7%, 48.8%, and 14.6%, 41.5%, 43.9%, respectively, with significant difference between the two groups (P=0.023). Logistic regression analysis revealed the V444A polymorphism (TC heterozygous mutation) was associated with PIS. Conclusion: ABCB11 gene polymorphism at the site of V444A may be related to the susceptibility of PIS.

Pancreatic stone protein - sepsis and the riddles of the exocrine pancreas.

Pancreatic stone protein (PSP), discovered in the 1970ies, was first associated with stone formation during chronic pancreatitis. Later, the same protein was independently detected in islet preparations and named regenerating protein 1 (REG1). Additional isoforms of PSP, including pancreatitis-associated protein (PAP), belong to the same protein family. Although the names indicate a potential function in stone formation or islet regeneration, involvements in cellular processes were only suggestive and never unequivocally proven. We established an association between PSP levels in patient blood samples and the development of sepsis. In this review, written in connection with receiving the Lifetime Achievement Award of the European Pancreatic Club, the evolution of the sepsis aspect of PSP is described. We conclude that the true functional properties of this fascinating pancreatic protein still remain an enigma.

Isolated 17, 20 Lyase Deficiency Secondary to a Novel CYB5A Variant: Comparison of Steroid Metabolomic Findings with Published Cases Provides Diagnostic Guidelines and Greater Insight into Its Biological Role.

OBJECTIVE: The objective of this study was to report CYB5A deficiency, to discuss the contribution of steroid metabolomics to diagnosis and interpretation, and to highlight the presence of testicular microlithiasis. METHODS: Two siblings with ambiguous genitalia at birth were later found to carry novel CYB5A variants, with resulting isolated 17, 20 lyase deficiency. We compared urine steroid data obtained between birth and adulthood with that from other cases. RESULTS: Neonatal urine steroid profiles show a relative increase of 16-hydroxylated pregnenolone metabolites. Thereafter, there are no distinguishing features until puberty, when sex steroid deficiency drives gonadotrophin production, resulting in marked increases of 17-hydroxyprogesterone metabolites derived from the gonads. This excess may be revealed pre-pubertally by gonadotrophin stimulation testing. Novel findings are first, a considerable capacity for DHEA synthesis in the neonatal period compared to childhood and adulthood, suggesting that DHEAS production is much less dependent on CYB5A at birth; second, no consistent change in "backdoor pathway" intermediates; third, side chain cleavage of cortisol is largely unaffected, supporting the existence of a different lyase not dependent on CYB5A; fourth, increased 17-hydroxyprogesterone metabolites and very low androgen metabolites are diagnostic post-pubertally. CONCLUSION: This is the fourth disease-causing variant in CYB5A in isolated 17, 20 lyase deficiency and the first associated with testicular microlithiasis. Establishing a biochemical diagnosis pre-pubertally should now be possible using urine steroid profiling, supported by synacthen and gonadotrophin stimulation testing. We recommend liquid chromatography-mass spectrometry/mass spectrometry rather than immunoassay for serum steroid analysis, early methaemoglobin measurement and surveillance should testicular microlithiasis be detected.

Genes associated with testicular germ cell tumors and testicular dysgenesis in patients with testicular microlithiasis.

Testicular microlithiasis (TM) is one of the symptoms of testicular dysgenesis syndrome (TDS). TM is particularly interesting as an informative marker of testicular germ cell tumors (TGCTs). KIT ligand gene (KITLG), BCL2 antagonist/killer 1 (BAK1), and sprouty RTK signaling antagonist 4 (SPRY4) genes are associated with a high risk of TGCTs, whereas bone morphogenetic protein 7 gene (BMP7), transforming growth factor beta receptor 3 gene (TGFBR3), and homeobox D cluster genes (HOXD) are related to TDS. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis, we investigated allele and genotype frequencies for KITLG (rs995030, rs1508595), SPRY4 (rs4624820, rs6897876), BAK1 (rs210138), BMP7 (rs388286), TGFBR3 (rs12082710), and HOXD (rs17198432) in 142 TGCT patients, 137 TM patients, and 153 fertile men (control group). We found significant differences in the KITLG GG_rs995030 genotype in TM (P = 0.01) and TGCT patients (P = 0.0005) compared with the control. We also revealed strong associations between KITLG_rs1508595 and TM (G allele, P = 0.003; GG genotype, P = 0.01) and between KITLG_rs1508595 and TGCTs (G allele, P = 0.0001; GG genotype, P = 0.0007). Moreover, there was a significant difference in BMP7_rs388286 between the TGCT group and the control (T allele, P = 0.00004; TT genotype, P = 0.00006) and between the TM group and the control (T allele, P = 0.04). HOXD also demonstrated a strong association with TGCTs (rs17198432 A allele, P = 0.0001; AA genotype, P = 0.001). Furthermore, significant differences were found between the TGCT group and the control in the BAK1_rs210138 G allele (P = 0.03) and the GG genotype (P = 0.01). KITLG and BMP7 genes, associated with the development of TGCTs, may also be related to TM. In summary, the KITLG GG_rs995030, GG_rs1508595, BMP7 TT_rs388286, HOXD AA_rs17198432, and BAK1 GG_rs210138 genotypes were associated with a high risk of TGCT development.

A case of Riley Ruvalcaba syndrome with a novel PTEN mutation accompanied by diffuse testicular microlithiasis and precocious puberty.

BACKGROUND: Bannayan Riley Ruvalcaba syndrome (BRRS) is exceedingly rare, with only about 50 reported cases to date. CASE PRESENTATION: We report a patient with hypoglycemia, precocious puberty and diffuse testicular microlithiasis accompanying BRRS, and think that this case is important in the light of a newly identified mutation in the PTEN gene. CONCLUSIONS: Close attention must be paid in terms of PTEN mutations in cases of macrocephaly and accompanying neurological and dermatological findings.

Genes associated with testicular germ cell tumors and testicular dysgenesis in patients with testicular microlithiasis / 亚洲男科学杂志(英文版)

Testicular microlithiasis (TM) is one of the symptoms of testicular dysgenesis syndrome (TDS). TM is particularly interesting as an informative marker of testicular germ cell tumors (TGCTs). KIT ligand gene (KITLG), BCL2 antagonist/killer 1 (BAK1), and sprouty RTK signaling antagonist 4 (SPRY4) genes are associated with a high risk of TGCTs, whereas bone morphogenetic protein 7 gene (BMP7), transforming growth factor beta receptor 3 gene (TGFBR3), and homeobox D cluster genes (HOXD) are related to TDS. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis, we investigated allele and genotype frequencies for KITLG (rs995030, rs1508595), SPRY4 (rs4624820, rs6897876), BAK1 (rs210138), BMP7 (rs388286), TGFBR3 (rs12082710), and HOXD (rs17198432) in 142 TGCT patients, 137 TM patients, and 153 fertile men (control group). We found significant differences in the KITLG GG_rs995030 genotype in TM (P = 0.01) and TGCT patients (P = 0.0005) compared with the control. We also revealed strong associations between KITLG_rs1508595 and TM (G allele, P = 0.003; GG genotype, P = 0.01) and between KITLG_rs1508595 and TGCTs (G allele, P = 0.0001; GG genotype, P = 0.0007). Moreover, there was a significant difference in BMP7_rs388286 between the TGCT group and the control (T allele, P = 0.00004; TT genotype, P = 0.00006) and between the TM group and the control (T allele, P = 0.04). HOXD also demonstrated a strong association with TGCTs (rs17198432 A allele, P = 0.0001; AA genotype, P = 0.001). Furthermore, significant differences were found between the TGCT group and the control in the BAK1_rs210138 G allele (P = 0.03) and the GG genotype (P = 0.01). KITLG and BMP7 genes, associated with the development of TGCTs, may also be related to TM. In summary, the KITLG GG_rs995030, GG_rs1508595, BMP7 TT_rs388286, HOXD AA_rs17198432, and BAK1 GG_rs210138 genotypes were associated with a high risk of TGCT development.

Bull's-eye pattern of pancreatic-duct stones on multidetector computed tomography and gene-mutation-associated pancreatitis (GMAP).

PURPOSE: This study prospectively assessed whether the presence of a bull's-eye pattern of pancreatic-duct stones on multidetector computed tomography (MDCT) correlated with gene-mutation-associated pancreatitis (GMAP) and whether other signs suggestive of GMAP can be detected with MDCT. MATERIALS AND METHODS: Forty-seven patients with chronic calcific pancreatitis underwent genetic testing for CFTR, SPINK1 and PRSS1 mutations and an MDCT scan of the abdomen. Qualitative analysis assessed the presence or absence of pancreatic-duct stones with bull's-eye appearance. Quantitative analysis included the number and maximum diameter of stones and the diameter of the main pancreatic duct. RESULTS: Fifteen of 47 patients (32%) were positive for gene mutations (GMAP patients). The bull's-eye pattern was found in 10/15 patients (67%) with GMAP and in 4/32 (12%) patients with chronic pancreatitis not associated with GMAP (NGMAP; p<0.0001). The mean diameter of duct stones was 15 mm in patients with GMAP and 10 mm in patients with NGMAP (p<0.04). CONCLUSIONS: The presence of duct stones with a bull's-eye pattern correlates with GMAP. Duct stones with diameter ≥15 mm are another sign suggestive of GMAP.

Por qué y cómo hemos de analizar los cálculos urinarios / Why and how we must analyse urinary calculi

Contexto: Existe una heterogeneidad de criterio sobre la utilidad del análisis del cálculo urinario, así como de cuál es la metodología más adecuada. En esta revisión se presenta el análisis de la litiasis mediante la técnica del estudio morfoconstitucional basada en la combinación de la microscopía estereoscópica (MEST) con el estudio de infrarrojos (EIR). Resumen de evidencia: Existen múltiples técnicas de análisis del cálculo: análisis químico, microscopía electrónica, difracción por rayos X, MEST y EIR. Mediante la revisión de cada una de estas técnicas y el estudio de varios casos clínicos, el presente trabajo muestra la utilidad clínica del análisis del cálculo, así como las ventajas e inconvenientes de cada uno de los citados métodos. Por otro lado, se evidencia cómo el análisis mediante el estudio morfoconstitucionales el que más información clínica de utilidad ofrece al urólogo. Asimismo, se presenta la clasificación de las litiasis basadas en este método y su correlación clínica con el paciente. Conclusiones: El análisis del cálculo mediante la técnica del estudio morfoconstitucional aporta más información que el resto de técnicas y permite establecer una clasificación del cálculo de gran utilidad clínica y diagnóstica (AU)

Context: There is heterogeneity of criteria on the utility of urinary stone analysis as well as on which is the most suitable methodology. This review presents the analysis of the lithiasis using the morphoconstitutional analysis technique based on the combination of the stereoscopic microscopy (SM) with infrared study (IRS). Summary of the evidence: There are many techniques to analyze the stone: chemical analysis, electron microscopy, X-ray diffraction, SM and IRS. Reviewing each one of these techniques and through the study of several clinical cases, this review shows the usefulness of stone analysis and the pros and cons of each one of the mentioned techniques. Furthermore, it can be clearly seen how the morphoconstitutional analysis is the one that offers the most useful clinical information to the urologist. In addition, classification of the lithiasis based on this method and its clinical correlation with patients is presented. Conclusions: Using the morphoconstitutional study to analyze the stone offers more information than the other techniques and it makes it possible to establish a stone classification of important clinical and diagnostic utility (AU)

A case of pulmonary alveolar microlithiasis with an intragenetic deletion in SLC34A2 detected by a genome-wide SNP study.

A case of pulmonary alveolar microlithiasis occurring in an inbred family is presented. A genome-wide analysis of the patient's genomic DNA using a high-density single nucleotide polymorphism (SNP) array revealed a small intragenetic mutation at SLC34A2. The results suggest that the high-density SNP array has the power to identify a recessive disease gene(s) even in the analysis of only a single inbred patient.

[Three cases of pulmonary alveolar microlithiasis in a family and clinical analysis].

OBJECTIVE: To describe the characteristics of 3 cases of pulmonary alveolar microlithiasis in a family, and therefore to improve the understanding of the disease. METHODS: To analyze the clinical, laboratory and radiological data of three patients with pulmonary alveolar microlithiasis in a family and the relevant literatures were reviewed. RESULTS: There was a typical manifestation in these three cases of pulmonary alveolar microlithiasis: progressive dyspnoea, cough, family history. Chest X-ray and computed tomography demonstrate: the pulmones was full of high density reflection of intra-alveolar microliths especially in middle-lower lobe and posterior lobe. The etiology of these three cases is still unknown, consanguineous marriage of parents is possible reason. There was not effective therapies to them. CONCLUSION: Pulmonary alveolar microlithiasis is a disease without clear known etiology and effective therapy. For a patient with radiological features of high density intra-alveolar microliths and a positive family history, the diagnosis should be highly suspected.

Familial pulmonary alveolar microlithiasis diagnosed by bronchoalveolar lavage. A case report.

BACKGROUND: Familial alveolar microlithiasis is a rare lung disease. In this study we describe the cytologic features of this disease in bronchoalveolar lavage. CASE: A 10-year-old girl and her uncle, a 50-year-old man, had dyspnea and diffuse interstitial pattern on chest radiograph with no defined cause at a period of 10 years apart. Open lung biopsy in the girl and transbronchial lung biopsy plus bronchoalveolar lavage (BAL) in the man were per-formed to determine the diagnosis. In cyopen lung biopsy the diagnosis was alveolar microlithiasis. BAL revealed rehtypical microliths (calcospherites), and th transbronchial lung biopsy performed in the same patient failed to disclose superficially reset any significant pathology. In cytologic a smears, extracellular and intracellular concentrically layered purple-brown, round-to-oval microliths were clearly seen. Cyanophilic periodic acid-Schiff positive intracytoplasmic amorphous material was also frequently seen in alveolar macrophages. CONCLUSION: Familial alveolar microlithiasis is a rare interstitial lung disease that can be easily diagnosed by BAL. This procedure is a very useful tool in diagnosing and classifying some interstitial lung diseases.

TFF peptides and mucins are major components of dacryoliths.

PURPOSE: The study was performed to determine whether trefoil factor peptides (TFF) and/or mucins are components of dacryoliths and to gain further insight into dacryolith composition and formation. METHODS: Twenty dacryoliths found in lacrimal surgery in patients suffering from primary acquired nasolacrimal duct obstruction were analyzed for the presence of TFF peptides (TFF1, 2, 3), mucins (MUC1, 2, 3, 4, 5AC, 5B, 6, 7, 8), defense cells (T- and B lymphocytes, macrophages, neutrophils), and antimicrobial substances (alpha defensins 1-3, secretory phospholipase A(2)) by means of light microscopy, histochemistry, immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR. RESULTS: All dacryoliths except one revealed clear immunoreactivity for all three TFF peptides. The immunohistochemical distribution of mucins was inhomogeneous throughout the different dacryoliths. However, in some dacryoliths all mucins investigated were detected. MUC8 showed reactivity in 14 out of 15 dacryoliths analyzed by immunohistochemistry. Most dacryoliths contained alpha defensins 1-3 as the secretory product of neutrophils. T and B lymphocytes, macrophages and secretory phospholipase A(2) were only present in single dacryoliths. Quantification of TFF peptide expression supported the immunohistochemical finding that all three TFF peptides are augmented in dacryoliths. CONCLUSIONS: Dacryoliths consist partly of secreted mucins comparable with the mucin spectrum of the epithelium of healthy nasolacrimal ducts. Beside TFF1 and TFF3, both of which are produced under healthy circumstances, TFF2 is additionally induced and secreted in cases of dacryolithiasis. All three TFF peptides appear to be augmented in dacryoliths. With regard to their rheologic properties, TFF peptides may play a functional role in dacryolith formation. However, our results raise the question of whether TFF peptides per se influence dacryolith formation or whether their secretion, as in secretion of mucins and alpha defensins 1-3, is merely a secondary phenomenon.

[Multiple enterolithiasis, coexisting with bladder and gallbladder lithiasis, associated with colon adenocarcinoma]. / Enterolitiasis múltiple, coexistiendo con litiasis biliar y vesical, asociada a adenocarcinoma de colon.

Enteroliths are calculi primarily formed in the intestine. Enterolithiasis is a rare condition frequently associated with intestinal stasis. Usually it causes no symptoms in most cases, but it can be an important diagnostic clue in patients presenting intestinal occlusive symptoms. We report a case of multiple enterolithiasis, very infrequent pathology, coexisting with bladder and gall bladder lithiasis in a patient with colon adenocarcinoma. Diagnosis was made by X-rays and CT images. Calculi were analysed by several methods: chemical, infrared spectroscopy, stereoscopic microscopy and atomic emission spectroscopy; they showed that caluli are made up of organic material and whilokita (calcium and magnesium ortophosphate). No risk factors for lithogenesis were found in this patient excluding the intestinal stasis caused by intestinal narrowing as a result of adenocarcinoma. Genetic factors are suggested as main contributors to hyperlithogenesis observed in this patient. The physiopathological conditions were studied in depth and literature about this subject reviewed.

Profiling of gene expression associated with hepatolithiasis by complementary DNA expression array.

By use of cDNA expression array method, we compared the expression profiles of genes in hepatolithiasis tissues with those of paired normal tissues. Expression of 1176 cancer related genes that include 33 tumor suppressor genes, 100 proto-oncogenes and 37 DNA damage repair genes were examined in this study. We found that expression of tumor suppressor genes and proto-oncogenes was systemically activated in hepatholithiasis tissues, suggesting that expression of genes controlling cell growth becomes unstable in liver lobe of hepatolithiasis. In contrast, expression of DNA damage repair genes were not activated but rather remained unchanged in hepatholithiasis tissues, suggesting that repair process is not strongly activated but rather impaired in hepatholithiasis tissues.

Pulmonary alveolar microlithiasis: clinical features, evolution of the phenotype, and review of the literature.

Pulmonary alveolar microlithiasis (PAM) (MIM 265100) is a rare, autosomal recessive pneumopathy characterized by intra-alveolar formation and accumulation of tiny, roundish corpuscles called "microliths". The name "alveolar microlithiasis" was first used by Puhr in 1933; since then, several reports have appeared, and over 300 individuals with this condition have been reported. We have reviewed the PAM cases in the literature in light of personal experience, focusing on medical implications, disease diagnosis and progression over time, familial predisposition, and geographical and sex distribution. This study confirms autosomal recessive inheritance and does not support the role of other, non-genetic, factors in the pathogenesis of PAM.

Genetic susceptibility to fibrocalculous pancreatic diabetes in Bangladeshi subjects: a family study.

Fibrocalculous pancreatic diabetes (FCPD) is an uncommon cause of diabetes, seen mainly in developing countries. A family-based study was carried out in 67 Bangladeshi families, consisting of a proband with FCPD and both parents, to determine whether an association exists between FCPD susceptibility and either the major histocompatiblity complex (MHC) or insulin gene (INS) loci. HLA-DQB1 typing was done using allele-specific primers, and INS was typed using the restriction enzyme HphI. Three microsatellites (TNFa, TNFc and TNFd), from within and flanking the TNF-LT locus, were used for MHC Class IV typing and a PCR-RFLP assay was used to define the -308G/A TNF promoter polymorphism. The extended transmission disequilibrium test (ETDT) was used for statistical analysis. An overall association was observed between FCPD and HLA-DQB1 (P = 0.003), that was largely due to a positive association with HLA-DQB1*0302 and a negative association with HLA-DQB1*0202. Although no association was found between FCPD and TNF-LT microsatellite markers a trend was observed for TNFc (P = 0.037, Pc = 0.15). No association was found between FCPD and INS (P = 0.26). This study confirms an association between FCPD and the MHC using a family-based study design and the stringent ETDT analysis; a novel protective association was found with HLA-DQB1*0202 in Bangladeshi FCPD subjects. The genetic susceptibility to FCPD has features both similar and dissimilar to T1DM.

Pulmonary alveolar microlithiasis: a rare familial inheritance with report of six cases in a family. Contribution of six new cases to the number of case reports in Turkey.

Pulmonary alveolar microlithiasis (PAM) is a lung disease characterized by deposits of calcium within the alveoli. Our aim was to emphasize the familial character and the clinical features of the disease, and to draw attention to the increasing number of Turkish patients reported in the world. We detected 6 cases of PAM. Three cases had been diagnosed 4 years earlier, and 3 new cases were detected during the screening of the family members. All patients were male and the mean age was 11.5 ranging between 5 and 29 years. Five of the patients were cousins and the other one was their uncle. Radiographic studies showed a sand-like appearance in all patients. One case showed small subpleural bullae and bronchiectatic changes in both lower lobes in recent high-resolution CT scans, while his CT performed 4 years ago showed only sand-like appearance. The cases were diagnosed with the demonstration of microliths by bronchoalveolar lavage in 5 patients and transbronchial biopsy in 1. Recently reported cases from Turkey have constituted a considerable percentage among all cases in the world. In conclusion, (1) our patients constitute one of the largest series of cases reported in one family in the world. The disease seems to have familial and racial characteristics. The Turkish race has to be further investigated for genetic transmission. (2) Contrary to female predominance in previous reports, all 6 cases were male and 5 of them were below 12 years of age. (3) The disorder may show rapid progression in some cases probably due to the severity of the genetic disturbance.

Radiolucent pancreatic lithiasis: a precursor stage for calcified pancreatic lithiasis or a new entity?

OBJECTIVE: Radiolucent pancreatic lithiasis (RPL) has been identified as a different entity from calcified pancreatic lithiasis. The purpose of this study is to evaluate the frequency, characteristics and evolution of RPL. PATIENTS: Between 1983 and 1995, 278 consecutive patients who presented with pancreatic lithiasis were studied. Forty-four patients had RPL (15.8%): 27 had pure radiolucent stones (PRS) (group 1), 5 had pure radiolucent stones combined with evenly calcified stones (ECS) (group 2), 2 had target calculi (TC) (radiolucent core with calcified shell) (group 3), 10 had TC combined with ECS (group 4). RESULTS: Among the 27 patients with PRS, there were 19 males with a mean age of 41 years. PRS were mainly located in the head of the pancreas with a mean diameter of 5 mm (range 3-26 mm). Seven patients among 27 with PRS (26%) were less than 20 years old (juvenile form) or more than 60 years old (senile form). They were characterized by no or low alcohol consumption and a high rate of attacks of acute pancreatitis. In group 1, PRS turned to more advanced calcified stages in 6/16 of patients (37%) followed in 30 to 144 months with a prior stage of TC in 2 cases. An evolution toward more calcified stages (TC or ECS) occurred in half of the patients belonging to group 2 and 4 in 36 to 84 months. Genetic disposition and alcohol consumption could account for the evolution toward more calcified stages. A genetic factor is suggested by a rapid evolution to evenly calcified stones in two aged children 8 and 10 years and by a high frequency of familial cases in patients belonging to groups 2 and 4 (60% and 20%) as compared to group 1 with PRS (4%). Alcohol consumption could accelerate the calcifying process since patients belonging to groups 2 and 4 had a significantly higher alcohol consumption than those with PRS (group 1). CONCLUSION: RPL is a heterogeneous pancreatic disease including juvenile and senile presentation which may represent about 15% of pancreatic lithiasis. Evolution towards calcified stages (PRS then TC then ECS) occurred in 37-50% of cases and could be related to a genetic factor and increased alcohol consumption.