Laurence-Moon-Biedl syndrome, associated with multiple genitourinary tract anomalies

Making sense of cilia in disease: the human ciliopathies

Ubiquitous in nature, cilia and flagella comprise nearly identical structures with similar functions. The most obvious example of the latter is motility: driving movement of the organism or particle flow across the epithelial surface in fixed structures. In vertebrates, such motile cilia are evident in the respiratory epithelia, ependyma, and oviducts. For over a century, non-motile cilia have been observed on the surface of most vertebrate cells but until recently their function has eluded us. Gathering evidence now points to critical roles for the mono-cilium in sensing the extracellular environment, and perturbation of this function gives rise to a predictable panoply of clinical problems. We review the common clinical phenotypes associated with ciliopathies and interrogate Online Mendelian Inheritance in Man (OMIM) to compile a comprehensive list of putative disorders in which ciliary dysfunction may play a role.

The cause of death in Laurence-Moon-Bardet-Biedl syndrome

The certificates of death of 14 deceased patients with Laurence-Moon-Bardet-Biedl (LMBB) syndrome, in which retinal dystrophy is dominant feature, were review. Death occurred at a considerably younger age than in the general population. Renal disease was noted as primary or contributing cause of death in 7 cases with the diagnoses: cyst of the kidney, renal sclerosis, renal failure, proteinuria, renal disease unspecified and malignant hypertension with renal involvement. It is concluded that renal involvement is characteristic of individuals with LMBB syndrome and seems to reduce life expectancy considerably.

New criteria for improved diagnosis of Bardet-Biedl syndrome: results of a population survey

Bardet-Biedl syndrome (BBS) is an autosomal recessive condition characterised by rod-cone dystrophy, postaxial polydactyly, central obesity, mental retardation, hypogonadism, and renal dysfunction. BBS expression varies both within and between families and diagnosis is often difficult. We sought to define the condition more clearly by studying 109 BBS patients and their families, the largest population surveyed to date. The average age at diagnosis was 9 years, which is late for such a debilitating condition, but the slow development of the clinical features of BBS probably accounts for this. Postaxial polydactyly had been present in 69% of patients at birth, but obesity had only begun to develop at around 2-3 years, and retinal degeneration had not become apparent until a mean age of 8.5 years. Our study identified some novel clinical features, including neurological, speech, and language deficits, behavioural traits, facial dysmorphism, and dental anomalies. In the light of these features we propose a revision of the diagnostic criteria, which may facilitate earlier diagnosis of this disorder. We present evidence for an overlapping phenotype with the Laurence-Moon syndrome and propose a unifying, descriptive label be adopted (polydactyly-obesity-kidney-eye syndrome).

 We report an increased prevalence of renal malformations and renal cell carcinoma in the unaffected relatives of BBS patients and suggest that these may be a consequence of heterozygosity for BBS genes. Our findings have important implications for the care of BBS patients and their unaffected relatives.

The importance of renal impairment in the natural history of Bardet-Biedl syndrome

Bardet-Biedl syndrome is a rare autosomal recessive disease characterized by dysphormic extremities, retinal dystrophy, obesity, hypogenitalism in males, and renal structural abnormalities. Because the clinical outcome of these patients is not well known, 21 families with Bardet-Biedl syndrome (BBS) were studied to determine the natural history of the disease. In a prospective cohort study, 38 patients with the syndrome and 58 unaffected siblings were identified. Patients were studied in 1987 and again in 1993. Age of onset of blindness, hypertension, diabetes, renal impairment, and death was determined. The prevalence of obesity, gonadal dysfunction, and renal structural abnormalities was assessed. All but 5 BBS patients (86%) were legally blind, 26% being blind by the age of 13 years and 50% by 18 years. Eighty-eight percent were above the 90th percentile for height and weight. Twenty-five (66%) patients had hypertension, 25% of BBS patients by age 26 years, and 50% by age 34 years, whereas in the unaffected group, 25% had hypertension by age 49 years (P < 0.0001). Twelve (32%) BBS patients developed diabetes mellitus, compared with none of the unaffected group. Only 2 patients were insulin dependent. Twenty-five percent of BBS patients had diabetes by the age of 35 years. In 12 women of reproductive age, 1 (8%) had primary gonadal failure. In 10 men, 4 had primary testicular failure. Nine (25%) patients developed renal impairment, with 25% of the BBS group affected by the age of 48 years. Imaging procedures of the kidney were performed in 25 patients with normal renal function. Whereas fetal lobulation and calyceal cysts/diverticula/clubbing were characteristic, occurring in 96% of patients, 20% (n = 5) had diffuse and 4% (n = 1) focal cortical loss. Eight patients with BBS died, 3 with end-stage renal failure and 3 with chronic renal failure. On life-table analysis, 25% of BBS patients had died by 44 years, whereas at that age 98% of unaffected siblings were still alive (P < 0.0001). Bardet-Biedl syndrome has an adverse prognosis, with early onset of blindness, obesity, hypertension, and diabetes mellitus. Renal impairment is frequent and an important cause of death. Survival is substantially reduced.

Obesity, hypertension, and renal disease in relatives of Bardet-Biedl syndrome sibs

The Bardet-Biedl syndrome is a rare autosomal recessive disorder characterized by pigmentary retinopathy, obesity, polydactyly, hypogonadism, and mental retardation. Renal abnormalities, hypertension, acquired heart disease, and hepatic fibrosis also occur in homozygotes. Two adult Bardet-Biedl sibs, a man with hypertension and cardiomegaly and a woman with biliary cirrhosis, and 75 relatives in 5 generations of the extended family were identified. Hospital records for major illnesses, death certificates, and autopsy reports were examined. The frequent observation of obesity, hypertension, diabetes mellitus, and renal disease in first-degree relatives, obligate gene carriers, and other blood relatives raise the possibility that Bardet-Biedl heterozygotes are also predisposed to these disorders.

Classification and evaluation of the obesities

Obesity is a condition of multifactorial etiology that can be associated with important health and functional consequences. Suggestions for the proper evaluation of obese patients have been presented along with brief descriptions of the rationales for their use. The evaluation protocol has been summarized in two algorithms to aid in the performance of a complete and organized work-up.

Visual acuities and dark-adapted thresholds of children with Bardet-Biedl syndrome

We studied the visual acuities and dark-adapted sensitivities of 12 children with Bardet-Biedl syndrome. All except one child, who was seen only once, were tested serially. In the first decade of life, all visual acuities were within 2 octaves of normal. All but two final visual acuities obtained from patients in their second and third decades were more than 2 octaves poorer than normal. Dark-adapted sensitivities of all patients were, or became, significantly less than normal even in those patients whose period of follow-up was limited to the first decade of life. Of the 11 patients measured serially, seven showed decreases in dark-adapted sensitivities of at least 0.5 log unit during the follow-up period, and the last measured sensitivities of all patients were at least 2 log units less than the normal mean.

Glomerulonephropathy of Laurence-Moon-Biedl syndrome

A patient with Laurence-Moon-Biedl syndrome and nephrotic range proteinuria is presented. Radiological investigation of the urinary tract revealed clubbed calyces but no evidence of obstruction or vesicoureteric reflux. Renal biopsy revealed occasional sclerotic glomeruli, extensive foot-process fusion and segmental glomerular basement membrane abnormalities with negative immunofluorescence for immunoglobulins and complement. Nephrotic proteinuria responded to steroid therapy but mild proteinuria persisted. The findings were consistent with minimal change nephropathy superimposed on the glomerular lesions of Lawrence-Moon-Biedl syndrome.

Chronic renal failure; an important feature of the Laurence-Moon-Biedl syndrome

Two cases of end stage renal failure occurring in association with the Laurence-Moon-Biedl syndrome are reported. Abnormalities in renal function and morphology are increasingly recognized in these patients in whom uraemia is an important cause of morbidity and early mortality. The presence of renal impairment, occurring as frequently as any of the pentad of features that characterize the syndrome, has important implications for the prognosis and long term management of these patients.

Histopathology of mitochondrial cytopathy and the Laurence-Moon-Biedl syndrome

Clinical and histopathological studies of two patients with distinctly different inherited juvenile retinal dystrophies indicate that the ocular defect in mitochondrial cytopathy involves the underlying pigment epithelium, whereas in the Laurence-Moon-Biedl syndrome the photoreceptor cells are primarily affected.

Cystic kidneys. Genetics, pathologic anatomy, clinical picture, and prenatal diagnosis

According to the classification of Osathanondh and Potter of cystic kidneys we give an overview of the different types of cystic changes taking genetic aspects into account. Usually pathoanatomic types do not represent genetic entities: All type I kidneys are transmitted in an autosomal recessive way with varying clinical symptoms; in rare cases they even present in adults. The relationship to "congenital hepatic fibrosis", "cystic liver", and to the "Caroli syndrome" is discussed. Type II kidneys are usually not genetic in origin; but they may occur as part of several syndromes. Rarely genetic factors might contribute to type II kidneys that may present as familial cases of Potter syndrome ("renal non-function syndrome"). Type IV kidneys, although different in their pathoanatomic picture can be regarded according to a common pathogenetic theory as part of the spectrum of malformations as in type II. Therefore the genetic interpretation of type II kidneys also applies to type IV lesions. Type III kidneys include autosomal dominant polycystic kidney disease. This type may already present in childhood; the first prenatal diagnosis by ultrasonography is described in detail. Furthermore type III changes are part of syndromes or non-hereditary malformation complexes, and often present only as mild manifestations. Diseases with isolated involvement of the medulla (juvenile nephronophthisis/medullary cystic disease) or cortex are described as part of the differential diagnosis, they are heterogeneous and genetically only partly understood. Syndromes with cystic kidneys are reviewed as well as the possibilities of prenatal diagnosis of cystic diseases. Reliable prenatal diagnosis is only possible in type II, and possible in some of the other types. The nosology is improved if genetic information is taken into account.

Urologic manifestations of Laurence-Moon-Biedl syndrome

Although uremia is the major cause of death in more than 30 per cent of patients with Laurence-Moon-Biedl syndrome, little attention has been paid to this rare syndrome in the urologic literature. We herein report on 3 patients with this syndrome.

Ocular and systemic manifestations of the Bardet-Biedl syndrome

Four women with the Bardet-Biedl syndrome had ophthalmoscopic findings compatible with a severe rod-cone degeneration. The patients were legally blind (visual acuity, 20/200 or worse) in one or both eyes before the age of 30 years. Two patients with early involvement had macular bull's-eye pigment epithelial changes. Two other patients had more advanced disease with geographic atrophy of the macular pigment epithelium and underlying choriocapillaris. Bone spicule formation was variable. Electrophysiologic findings were consistent with severe derangement of both the rod and cone systems. All four patients had intraretinal capillary leakage along the vascular arcades and from the optic nerve without cystoid macular edema. Extensive endocrinologic evaluation showed no objective evidence of hypogenitalism in the three patients tested. Three patients had renal disease, secondary to vesicoureteral reflux, or hypertension, or both.

Virilism as a late manifestation in the Bardet-Biedl syndrome

The second case of virilism as a late manifestation of Bardet-Biedl syndrome (BBS) is described, with endocrine and histological evaluation. Both cases manifested ovulatory cycles and developed virilism in adulthood. Elevated plasma testosterone and 17-OH-progesterone were not suppressed by dexamethasone but were suppressed by medroxyprogesterone acetate. Peripheral and ovarian venous blood obtained at the time of surgery demonstrated a marked gradient for testosterone in both ovaries and for progesterone in the ovary bearing the corpus luteum. Histological evaluation of the ovaries demonstrated bilateral ovarian stromal hyperplasia with focal hyperthecosis. Bilateral ovariectomy resulted in complete correction of the endocrine abnormality, although the established hirsutism remains a mark of previous androgen excess.

The syndromology of anorectal malformation (atresia, stenosis, ectopia)

The syndromes, associations, and developmental field defects that include anorectal dysgenesis (atresia, stenosis, ectopia) as a principal or facultative sign are discussed. Most of these disorders are identifiable by their genetic or teratogenic etiology, their distinctive phenotype, or both. Their precise diagnosis is crucial for estimation of recurrence risk and other aspects of reproductive counseling, and it is essential for classificatory progress. The "VACTERL association" should not be used to label a patient with anorectal malformation and other anomalies except by exclusion; this rule is particularly relevant when the patient lacks tracheoesophageal malformation. The degree (or variety) of anorectal malformation that occurs in a given pattern of multiple congenital anomalies may be inconstant. Furthermore, anorectal malformation may be a solitary expression of a familial syndrome.

Renal histopathological changes in a child with Laurence-Moon-Biedl syndrome

This report describes a case of Laurence-Moon-Biedl syndrome identified in a 24-month-old boy. Significant renal involvement was present with right-sided vesicoureteral reflux, cystocele, urinary tract infections, and growth arrest of the right kidney. After the development of hypertension a left renal biopsy was performed to determine if bilateral renal disease was present. Histopathological and ultrastructural changes in the left kidney are described. These changes appear to be unrelated to pyelonephritis or hypertension and to be most consistent with the nephropathy of Laurence-Moon-Biedl syndrome.

The Laurence-Moon-Biedl syndrome in a Singhalese family

The first published occurrence of the Laurence-Moon-Biedl Syndrome in a Singhalese family is reported. Three members of a family of six with first cousin non-affected parents are described along with studies to indicate that the hypogonadism in this family can be ascribed to hypogonadotrophism. The high incidence of congenital heart disease and genito-urinary abnormalities noted by other is confirmed.

The renal lesion of the Laurence-Moon-Biedl syndrome

In nine children with the Laurence-Moon-Biedl syndrome a high incidence of nephropathy was documented. Renal involvement was noted in seven patients before or simultaneously with the diagnosis of LMBS. Five have uremia and two have died. All patients had an abnormal urogrum. The spectrum of renal lesions ranged from mesangial tissue proliferation to glomerular clerosis, interstitial scarring, and medullary and cortical cyst formation. A relationship between the lesions seen in the LMBS and those of other hereditary retinal-renal conditions is suggested.