Joubert Syndrome: Ophthalmological Findings in Correlation with Genotype and Hepatorenal Disease in 99 Patients Prospectively Evaluated at a Single Center.

PURPOSE: Joubert syndrome (JS) is caused by mutations in >34 genes that encode proteins involved with primary (nonmotile) cilia and the cilium basal body. This study describes the varying ocular phenotypes in JS patients, with correlation to systemic findings and genotype. DESIGN: Patients were systematically and prospectively examined at the National Institutes of Health (NIH) Clinical Center in the setting of a dedicated natural history clinical trial. PARTICIPANTS: Ninety-nine patients with JS examined at a single center. METHODS: All patients underwent genotyping for JS, followed by complete age-appropriate ophthalmic examinations at the NIH Clinical Center, including visual acuity (VA), fixation behavior, lid position, motility assessment, slit-lamp biomicroscopy, dilated fundus examination with an indirect ophthalmoscope, and retinoscopy. Color and fundus autofluorescence imaging, Optos wide-field photography (Dunfermline, Scotland, UK), and electroretinography (ERG) were performed when possible. MAIN OUTCOME MEASURES: The VA (with longitudinal follow-up where possible), ptosis, extraocular muscle function, retinal and optic nerve status, and retinal function as measured by ERG. RESULTS: Among patients with JS with quantifiable VA (68/99), values ranged from 0 logarithm of the minimum angle of resolution (logMAR) (Snellen 20/20) to 1.5 logMAR (Snellen 20/632). Strabismus (71/98), nystagmus (66/99), oculomotor apraxia (60/77), ptosis (30/98), coloboma (28/99), retinal degeneration (20/83), and optic nerve atrophy (8/86) were identified. CONCLUSIONS: We recommend regular monitoring for ophthalmological manifestations of JS beginning soon after birth or diagnosis. We demonstrate delayed visual development and note that the amblyogenic time frame may last significantly longer in JS than is typical. In general, patients with coloboma were less likely to display retinal degeneration, and those with retinal degeneration did not have coloboma. Severe retinal degeneration that is early and aggressive is seen in disease caused by specific genes, such as CEP290- and AHI1-associated JS. Retinal degeneration in INPP5E-, MKS1-, and NPHP1-associated JS was generally milder. Finally, ptosis surgery can be helpful in a subset of patients with JS; decisions as to timing and benefit/risk ratio need to be made on an individual basis according to expert consultation.

An ovine hepatorenal fibrocystic model of a Meckel-like syndrome associated with dysmorphic primary cilia and TMEM67 mutations.

Meckel syndrome (MKS) is an inherited autosomal recessive hepatorenal fibrocystic syndrome, caused by mutations in TMEM67, characterized by occipital encephalocoele, renal cysts, hepatic fibrosis, and polydactyly. Here we describe an ovine model of MKS, with kidney and liver abnormalities, without polydactyly or occipital encephalocoele. Homozygous missense p.(Ile681Asn; Ile687Ser) mutations identified in ovine TMEM67 were pathogenic in zebrafish phenotype rescue assays. Meckelin protein was expressed in affected and unaffected kidney epithelial cells by immunoblotting, and in primary cilia of lamb kidney cyst epithelial cells by immunofluorescence. In contrast to primary cilia of relatively consistent length and morphology in unaffected kidney cells, those of affected cyst-lining cells displayed a range of short and extremely long cilia, as well as abnormal morphologies, such as bulbous regions along the axoneme. Putative cilia fragments were also consistently located within the cyst luminal contents. The abnormal ciliary phenotype was further confirmed in cultured interstitial fibroblasts from affected kidneys. These primary cilia dysmorphologies and length control defects were significantly greater in affected cells compared to unaffected controls. In conclusion, we describe abnormalities involving primary cilia length and morphology in the first reported example of a large animal model of MKS, in which we have identified TMEM67 mutations.

Association of arginine vasopressin receptor 1a gene polymorphisms with hepatorenal syndrome.

OBJECTIVE: To assess the association of arginine vasopressin receptor 1a gene single nucleotide polymorphisms with type I hepatorenal syndrome. METHODS: The case-control study was conducted at the Hangzhou City Xixi Hospital, Hangzhou, China, from January 2012 to June 2014, and comprised patients with type I hepatorenal syndrome and individuals with cirrhosis who acted as the control group. Arginine vasopressin receptor 1a gene rs113481894 locus single nucleotide polymorphisms were analysed by high-resolution melting methods. Statistical analysis was performed using SPSS 17. RESULTS: Of the 60 participants, 28(46.7%) were in the hepatorenal syndrome group and 32(53.3%) were controls. The mean age was 42.21±11.30years in the hepatorenal syndrome group and 43.69±12.60in the control group (p=0.64). Mean total bilirubin, albumin and prothrombin activity levels were 154.76±51.58, 49.30±24.67 and 33.42±3.69 in the hepatorenal syndrome group compared to 181.26±64.46, 41.78±17.52 and32.98±4.81among controls (p=0.09, p=0.18 and p=0.70). Statistically significant differences were found in the distributions of arginine vasopressin receptor 1a gene rs113481894 locus T allele between type I hepatorenal syndrome patients and the control group (odds ratio= 2.230; p= 0.040). CONCLUSIONS: T allele located at arginine vasopressin receptor 1a receptor promoter rs113481894 locus may be associated with the pathogenesis of type I hepatorenal syndrome.

Hyperbilirubinemia and rapid fatal hepatic failure in severe combined immunodeficiency caused by adenosine deaminase deficiency (ADA-SCID).

Adenosin deaminase (ADA) deficiency is the cause for Severe Combined Immunodeficiency (SCID) in about 15% of patients with SCID, often presenting as T (-)B (-)NK (-)SCID. Treatment options for ADA-SCID are enzyme replacement, bone marrow transplantation or gene therapy. We here describe the first patient with ADA-SCID and fatal hepatic failure despite bone marrow transplantation from a 10/10 HLA identical related donor. As patients with ADA-SCID may be at yet underestimated increased risk for rapid hepatic failure we speculate whether hepatitis in ADA-SCID should lead to the immediate treatment with enzyme replacement by pegylated ADA.

[Correlative study between angiotensin-converting enzyme gene polymorphism and hepatorenal syndrome].

OBJECTIVE: To investigate the relationship between insertion/deletion (I/D) polymorphism of angiotensin-converting enzyme (ACE) gene and uncompensated cirrhosis of liver with hepatorenal syndrome (HRS). METHODS: ACE I/D polymorphism was detected by polymerase chain reaction amplification of DNA fragment in 56 patients of uncompensated liver cirrhosis with HRS, and 60 healthy individuals served as the controls. At the same time, alanine aminotransferase, aspartate transaminase, serum creatinine (SCr), blood urea nitrogen (BUN) and glomerular filtration rate (GFR) etc. were measured in all the subjects, and the difference between these variables among different genotypes was noted. RESULTS: There was no significant difference in genotypes and allele frequency between the HRS group and controls(all P>0.05). The I allele frequency was higher than the D allele in all the subjects (all P<0.01). But in the control group, there was no significant difference in the genotype frequency among three genomic groups, while the II genotype frequency was higher than the one of ID and DD (all P<0.05). SCr and BUN of the II genotype were higher in the HRS group than that of ID and DD(both P<0.05) and GFR of the II genotype was lower than the one of ID and DD in the HRS group(P<0.05). CONCLUSION: There is relationship between ACE gene polymorphism and the incidence of uncompensated liver cirrhosis with HRS. II genotype may be the genetic factor of vulnerability to HRS patients with uncompensated cirrhosis of liver. The degree of kidney failure in II genotype population is more serious than in ID and DD individuals with uncompensated liver cirrhosis complicated by HRS.

Pathogenetic factors and clinical elements in ascites and hepatorenal syndrome during liver cirrhosis.

Ascites is the most frequent major complication of liver cirrhosis. Even if a significant decrease in renal clearances may be observed in the first stages of chronic active hepatitis, true renal impairment, often with the typical signs of hepatorenal syndrome, only occurs in patients with ascites, especially when tense and refractory. Experimental and clinical data suggest the presence of primary sodium and water retention, perhaps as a consequence of an increase in intrahepatic hydrostatic pressure. The abnormal sodium retention leads to plasma volume expansion, followed by decreased peripheral vascular resistances and increased cardiac output. This second stage concords with the peripheral arterial vasodilation theory, characterized by an increase in total blood volume, but with a decrease in effective arterial blood volume. This discrepancy leads to the activation of sympathetic nervous and renin-angiotensin-aldosterone systems. This activation, while protective against splanchnic and systemic vasodilation, provoked by the increased availability of nitric oxide and other vasodilating substances, induces renal vasoconstriction. This phenomenon can be considered as the basis of the progressive renal failure that leads to hepatorenal syndrome, favored by progressive exhaustion of the renal autacoid vasodilating substances. The first therapeutic approach to ascites is sequential and based on diuretic administration. Subsequently, paracentesis with albumin infusion is carried out, as well as transjugular intrahepatic portosystemic shunting, surgical portosystemic shunting, and liver transplantation: these procedures are essential for the treatment of hepatorenal syndrome.

Infantile Refsum disease: an inherited peroxisomal disorder. Comparison with Zellweger syndrome and neonatal adrenoleukodystrophy.

Three patients affected by infantile Refsum disease are described with mental retardation, minor facial dysmorphia, chorioretinopathy, sensorineural hearing deficit, hepatomegaly, failure to thrive and hypocholesterolaemia. Initially, only an accumulation of phytanic acid was thought to be present. More recent findings showed a biochemical profile very similar to that found in classical Zellweger syndrome or neonatal adrenoleukodystrophy. Morphologically typical peroxisomes were absent in the liver. All three disorders are associated with multiple peroxisomal dysfunction. Because of these similarities pertinent clinical data of our three patients are compared with those of reported patients diagnosed as having infantile Refsum disease, neonatal adrenoleukodystrophy or Zellweger syndrome who survived for several years. Attention is drawn to the difference in severity of clinical features, ranging from infantile Refsum's disease to neonatal adrenoleukodystrophy and, finally, to Zellweger syndrome.