Familial iron overload with possible autosomal dominant inheritance

A 96 member Melanesian kindred with 31 cases of iron overload is reported. Liver biopsies from 19 of these patients showed features similar to those of genetic haemochromatosis in Caucasians, but in contrast to the previous reported HLA-linked autosomal recessive pattern of inheritance for haemochromatosis, this family shows a pattern that is most consistent with autosomal dominant inheritance. This is suggested by involvement of three and possibly four consecutive generations, with a high frequency of transmission from parents to children and equal gender distribution. Linkage and segregation analysis supported dominant inheritance, with no demonstrable HLA linkage.     

Familial sinus node dysfunction with autosomal dominant inheritance.

A large family with sinus node dysfunction is described, spanning three generations and with an autosomal dominant trait. There was an obvious association between the grade of mental retardation and the severity of the sinoatrial disorder.     

Familial central precocious puberty suggests autosomal dominant inheritance

The prevalence of precocious puberty is higher in certain ethnic groups, and some cases may be familial. The aim of this study was to investigate the mode of inheritance of familial precocious puberty and to identify characteristics that distinguish familial from isolated precocious puberty. Of the 453 children referred to our center for suspected precocious puberty between January 1, 1997, and December 31, 2000, 156 (147 girls and 9 boys) were found to have idiopathic central precocious puberty, which was familial in 43 (42 girls and 1 boy) (27.5%). Data of the familial and sporadic cases were compared. The familial group was characterized by a significantly lower maternal age at menarche than the sporadic group (mean, 11.47 +/- 1.96 vs. 12.66 +/- 1.18 yr; P = 0.0001) and more advanced puberty at admission (Tanner stage 2, 56.5% vs. 78.1%; P = 0.006). Segregation analysis was used to study the mode of inheritance. The segregation ratio for precocious puberty was 0.38 (0.45 after exclusion of young siblings) assuming incomplete penetrance and 0.58 (0.65 after exclusion of young siblings) assuming complete ascertainment. These results suggest autosomal dominant transmission with incomplete, sex-dependent penetrance.     

Familial pulmonary hypertension. Evidence of autosomal dominant inheritance

A patient with primary pulmonary hypertension is the fourth member of a family proven to have the disease. The patient's father married twice; the disease appeared in both families, and was transmitted through two generations. Multiple genetic and environmental factors may result in pulmonary hypertension, but the distribution of cases in this family and in others reported is consistent with the autosomal dominant inheritance of a single genetic trait.     

Familial atrioventricular heart block; an autosomal dominant trait.

A family of 28 individuals spanning four generations was investigated because of a finding of complete heart block in five members and the existence of a low degree of atrioventricular (A-V) heart block in a sixth member. The disorder was characterized by 1) adult onset in all, 2) complete A-V heart block in five and first degree A-V heart block in one, 3) sinus bradycardia in three, 4) atrial fibrillation in five, 5) abnormal QRS complex in five, 6) ventricular tachycardia in three, 7) left ventricular enlargement in all, and 8) mitral insufficiency in five. Proximal location of the A-V heart block was suggested by the fact that atropine caused acceleration of the ventricular rate and by the presence of a His bundle potential preceding the QRS complexes. Involvement of the distal conducting system was indicated by the widened QRS complex and a prolonged H-V interval. Pathologic examination in one case showed extensive sinus node fibrosis and interruption of the A-V node-His bundle connection. This disorder is probably due to an autosomal dominant trait.     

Familial pulmonary hypertension. Evidence of autosomal dominant inheritance.

A patient with primary pulmonary hypertension is the fourth member of a family proven to have the disease. The patient's father married twice; the disease appeared in both families, and was transmitted through two generations. Multiple genetic and environmental factors may result in pulmonary hypertension, but the distribution of cases in this family and in others reported is consistent with the autosomal dominant inheritance of a single genetic trait.     

Familial visceral neuropathy with neuronal intranuclear inclusions: diagnosis by rectal biopsy.

A family with a visceral neuropathy manifested as chronic idiopathic intestinal pseudo-obstruction is reported. Diagnoses were made histologically by simple rectal biopsy. Discrete eosinophilic intranuclear inclusions, diagnostic of a disease known as neuronal intranuclear inclusion disease, were found in the submucosal ganglion cells. Abnormalities of the autonomic nervous system were identified by pupillary examination and electroretinography. In this family, three of four siblings were affected by the disease, which is apparently transmitted from the paternal side. This pedigree was unique for several reasons: (a) diagnosis in multiple members of two generations indicates that this familial visceral neuropathy was expressed in an autosomal dominant manner, (b) central autonomic nervous system abnormalities were detected by eye examination, and (c) the definitive pathological diagnosis was established antemortem by rectal biopsy in all cases.     

Genetic transmission of tumoral calcinosis: autosomal dominant with variable clinical expressivity

Tumoral calcinosis is a rare inherited metabolic disorder characterized by hyperphosphatemia, elevated serum 1,25-dihydroxyvitamin D levels and periarticular cystic and solid calcifications. Based on previous investigations, the inheritance of this disorder has been postulated to be autosomal recessive. This interpretation was based on finding clinically affected subjects in only single generations of kindreds. We investigated four generations of an affected kindred and found nine subjects with the disease. A unique dental lesion which is specific for this disorder and serves as a phenotypic marker was identified in two generations of the kindred. In all affected subjects, elevated serum 1,25-dihydroxyvitamin D levels were found, although each member did not have the classical clinical findings of tumoral calcinosis. The possibility that this disorder may be variably expressed and have multiple formes frustes has not been previously considered. Using the unique dental lesion as well as the classical clinical and biochemical abnormalities, we found that in this kindred, tumoral calcinosis is transmitted in an autosomal dominant mode, with variable clinical expressivity.     

Genetic thrombocytopenia with autosomal dominant transmission: a review of 54 cases

On the basis of a retrospective study of 3600 platelet kinetic studies, we have isolated 54 cases with chronic thrombocytopenia, a normal autologous and homologous platelet lifespan, and increased mean platelet volume without Döhle bodies, the absence of any functional platelet abnormalities, and a normal megakaryocyte count. These cases were either discovered during the first few years of life (i.e. constitutional) and/or were proven to be familial (autosomal dominant transmission). Previous treatments (corti-costeroids, immunoglobulins, androgens, immunosuppres-sor agents, splenectomy) were not effective in any of these cases or in their relatives. A new syndrome can therefore be proposed which can easily be suspected on the basis of platelet kinetic studies performed in cases of early onset, increased platelet volume, failure of corticosteroids or evidence of a familial blood disorder. It can be proved when the autologous platelet life span is demonstrated to be normal in spite of a chronic thrombocytopenia and a normal megakaryocytic count. The recognition of this syndrome will avoid neonatal complications (cephal-haematomas), surgical complications, and the use of expensive and possibly harmful ineffective treatments, both in the propositus and in other abnormal family members. The syndrome is certainly frequent (54 cases are presented here), but the diagnosis is often missed or delayed due to the low risk of haemorrhage. However, it is associated with a certain risk of leukaemia (four cases in three families).     

Chronic isolated macrothrombocytopenia with autosomal dominant transmission: a morphological and qualitative platelet disorder

Abstract: We studied 47 subjects belonging to 13 unrelated families with a history of mild haemorrhagic diathesis and chronic thrombocytopenia. 36 patients presented some degree of thrombocytopenia: 7/36 (19%) had slight thrombocytopenia (100–150×10⁹/L); 26/36 (72%) had mild thrombocytopenia (50–100×10⁹/L) and 3/36 (8%) had severe thrombocytopenia (<50×10⁹/L). No correlation was observed between platelet count and the degree of haemorrhagic diathesis, which was mild in the majority of patients. Transmission was autosomal dominant. Platelet anisocytosis, increased percentage of large platelets and absence of leukocyte inclusions were observed in 26/30 (87%) of the examined blood smears. The ultrastructural appearance of platelets was normal. Megakaryocytes appeared normal in number in 10/10 patients, but showed asynchronous nuclear-cytoplasm maturation and mainly nonlobulated nuclei. Platelet aggregation was studied in 26 patients and either increased or decreased curves were variably observed in response to different aggregating agents. Platelet-associated IgG (PAIgG) was increased in 18/31 (58%) patients, while serum autoantibodies against platelet glycoproteins Ib/IX or IIb/IIIa were demonstrable in only 1 case. An increased expression of platelet surface glycoproteins Ib and IIb/IIIa, as studied by murine monoclonal antibodies binding in 17 cases, was observed. Platelet survival performed by 111In-oxine-labelled autologous platelets was normal in the 3 studied patients. Congenital macrothrombocytopenia confirms to be a distinct clinical disorder for which the name of “chronic isolated hereditary macrothrombocytopenia” is proposed.     

Familial enteric neuropathy with pseudoobstruction

We report a case of autosomal dominant chronic intestinal pseudoobstruction secondary to a familial enteric neuropathy. Esophagogastrointestinal manometry studies in the index case showed decreased postprandial contractile frequency with normal amplitude of pressure activity in the stomach and small bowel. Pupillary function and autonomic reflexes were all normal, excluding an extrinsic autonomic neuropathy of the viscera. Histologic examination of the small intestine by hematoxylin and eosin stains revealed normal smooth muscles but a reduced number of neurons in the myenteric plexus without inflammatory cells or neuroNal intranuclear inclusions. Histologic examination of the myenteric plexus using the sections taken along the longitudinal axis of the intestine, stained with silver by the Smith technique, disclosed decreased numbers of argyrophilic neurons and degeneration of neurons and axons; however, there was no reactive increase in the number of glial cell nuclei. The patient's mother had suffered from chronic intestinal pseudoobstruction, which did not abate following extensive small bowel resection. This is the third family reported with an autosomal dominant enteric neuropathy unassociated with evidence of extrinsic autonomic or peripheral neuropathy. Subtotal resection of the small bowel was followed by recurrence of the pseudoobstruction syndrome in both affected members of the family.     

Familial visceral myopathy

A family with the autosomal dominant form of familial visceral myopathy is described involving four generations. The members illustrate several different clinical presentations including severe constipation, diarrhea, alternating constipation and diarrhea, volvulus, urinary tract infection, and retention of urine. One patient's history suggested that the uterus may have been involved. Diagnosis of this rare disease requires an awareness of the variable presentation and a careful histological examination of full-thickness sections of bowel. The potential pitfalls in both histological and clinical diagnosis of this condition are demonstrated in this family's history. The extensive involvement of small and large bowel in at least two family members is unusual in the autosomal dominant form of the disease, but their course has so far been favorable, lending further evidence to the impression that prognosis is good. This is of importance for genetic counseling of families who have this very rare disease.     

Familial hiatal hernia in a large five generation family confirming true autosomal dominant inheritance

BACKGROUND: Familial hiatal hernia has only rarely been documented. AIMS: To describe the pattern of inheritance of familial hiatal hernia within an affected family. SUBJECTS: Thirty eight members of a family pedigree across five generations. METHODS: All family members were interviewed and investigated by barium meal for evidence of a hiatal hernia. RESULTS: Twenty three of 38 family members had radiological evidence of a hiatal hernia. No individual with a hiatal hernia was born to unaffected parents. In one case direct male to male transmission was shown. CONCLUSIONS: Familial inheritance of hiatal hernia does occur. Evidence of direct male to male transmission points to an autosomal dominant mode of inheritance.     

Familial cutaneous malignant melanoma: autosomal dominant trait possibly linked to the Rh locus.

Segregation and linkage analyses were undertaken in families with multiple cases of cutaneous malignant melanoma (CMM) and a recently-described melanoma precursor, the dysplastic nevus syndrome (DNS). Clinical and laboratory data, including 23 genetic markers, were collected on 401 members of 14 high-risk kindreds. Pedigree analysis was compatible with an autosomal dominant mode of inheritance for the familial CMM trait. Although a similar model probably applies to the DNS trait as well, segregation analysis could not confirm the presence of a major locus. However, linkage analysis suggested that an autosomal dominant model was appropriate for the DNS, and that a DNS/CMM susceptibility gene may be located on the short arm of chromosome 1, within 30 map units of the Rh locus [maximum logarithm of odds (lod) score = 2.00].     

A diabetic visceral neuropathy

The article concentrates on an issue of a diabetic autonomous neuropathy (DAN) in the gastrointestinal tract (GIT). It points out etiopathogenesis of diabetic polyneuropathy. It presents autonomous neuropathy in an overview where it also in more detail discusses this issue in the GIT. It highlights clinical picture and possible diagnostic and therapeutic ways of affecting individual parts of the gastrointestinal tract.