Problems in managing patients with long QT syndrome and implantable cardioverter defibrillators: a report of two cases

Implantable cardioverter-defibrillators (ICDs) have been a successful adjunct to the management of arrhythmias in patients with Long QT syndrome (LQTS). In two patients, interactions between LQTS and the ICD were diagnosed and corrected. Oversensing of T waves was confirmed in the first, while in the second, the arrhythmia disappeared when T wave abnormalities improved after cessation of H2 blocker therapy. In patients with LQTS and an ICD, T wave oversensing should be considered. Interventions that may have an adverse effect on repolarization should be avoided.     

Left pulmonary artery sling: diagnosis and delineation of associated tracheobronchial anomalies with MR

BACKGROUND: The left pulmonary artery sling anomaly (SLPA) has generated controversy about its diagnosis, imaging and management particularly with regard to associated tracheobronchial anomalies. Objective. To evaluate the role of MR imaging in defining airway and vascular relationships in SLPA. MATERIALS AND METHODS: Retrospective review of the imaging and clinical records of three children with SLPA who underwent MRI including three dimensional image reconstruction. MR was compared and correlated with other imaging methods: plain chest radiographs (3); bronchoscopy (3); barium esophagram (1); echocardiography (2); cineangiography (2). RESULTS: MRI was vastly superior to other methods for clearly depicting airway and vascular anatomy and interrelationships. Good quality imaging and safe sedation was easily achieved in young infants. MR also provided accurate noninvasive evaluation of the reconstructed pulmonary artery and airway postoperatively. CONCLUSION: MR is capable of differentiating the two subtypes of SLPA. Specific delineation of vascular and airway anatomy and spatial relationships is essential for surgical management: reimplantation of LPA in type I and both LPA reimplantation and airway reconstruction in type II because of associated long segment airway stenosis.     

Constitutional chromosome anomalies in patients with cerebral gigantism (Sotos syndrome)

Two boys are presented with the clinical features of cerebral gigantism and chromosomal variants which have not been described so far in this syndrome. In the first boy a de novo pericentric inversion of chromosome Y was found, the karyotypes of all other investigated family members were normal. The patient had an obstructive hypertrophic cardiomyopathy and atrial septal defect type II. The second boy had inherited pericentric inversion of the heterochromatic region of chromosome 9 from his mother. This chromosome 9 variant was also found in his sister who had a similar phenotype but without gigantism. Endocrine evaluation demonstrated normal results in both boys. The intellectual achievement in both cases was average.     

Renal failure in two patients with Wolfram syndrome

BACKGROUND/OBJECTIVE: Aluminium is produced from the mineral bauxite. Occupational exposure is reported during the industrial processing of aluminium and is associated with pulmonary and neurotoxicity. However, data on exposure and toxicity of workers in the open bauxite mining industry do not exist. Therefore, a study was performed to explore aluminium exposure in employees involved in this bauxite mining process in a Surinam mine. METHODS/DESIGN: A group of workers occupationally exposed to aluminium in an open bauxite mine were compared with a group of nonexposed wood processors. Serum aluminium was analyzed using atomic absorption spectrometry Data from the clinical chemistry of the blood and a questionnaire were used to explore determinants for aluminium exposure. RESULTS: No significant difference between serum aluminium in the exposed (4.4 +/- 2.0 micrograms/L, n = 27) and control group (5.1 +/- 1.5 micrograms/L, n = 27) was detected. For the serum concentration of the clinical chemical variables (calcium, citrate, and creatinine), a statistically significant difference was computed (p < or = 0.02) between the exposed and control group. All levels were slightly higher in the exposed group; no statistically significant correlations with serum aluminium were found. CONCLUSIONS: In this study, serum aluminium values were in the normal range, no significant difference between the groups could be detected despite long-term occupational exposure.     

Further delineation of renal-coloboma syndrome in patients with extreme variability of phenotype and identical PAX2 mutations

Renal-coloboma syndrome is a recently described autosomal dominant syndrome of abnormal optic nerve and renal development. Two families have been reported with renal-coloboma syndrome and mutations of the PAX2 gene. The PAX2 gene, which encodes a DNA-binding protein, is expressed in the developing ear, CNS, eye, and urogenital tract. Ocular and/or renal abnormalities have been consistently noted in the five reports of patients with renal-coloboma syndrome, to date, but PAX2 expression patterns suggest that auditory and CNS abnormalities may be additional features of renal-coloboma syndrome. To determine whether additional clinical features are associated with PAX2 mutations, we have used PCR-SSCP to identify PAX2 gene mutations in patients. We report here four patients with mutations in exon 2, one of whom has severe ocular and renal disease, microcephaly, and retardation, and another who has ocular and renal disease with high-frequency hearing loss. Unexpectedly, extreme variability in clinical presentation was observed between a mother, her son, and an unrelated patient, all of whom had the same PAX2 mutation as previously described in two siblings with renal-coloboma syndrome. These results suggest that a sequence of seven Gs in PAX2 exon 2 may be particularly prone to mutation.     

Norrie-Warburg syndrome: two novel mutations in patients with classical clinical phenotype

Norrie-Warburg syndrome (NWS) is a rare X-linked disorder characterized by blindness, which is invariable, deafness and mental disturbances, which are present occasionally. We describe here two novel mutations, a missense mutation (C126S) and a 1-base pair insertion (insT466/T467), together with a recurrent mutation (M1V), found in patients presenting with the classical clinical phenotype of NWS. All three mutations are likely to result in prominent structural changes of the norrin protein.     

Apparently new syndrome of short stature, lumbar malsegmentation, and minor facial anomalies in two brothers

We describe a previously unrecognized syndrome in two brothers with short stature, webbed neck, unusual face, moderate malsegmentation of the lumbar spine, and unilateral Legg-Perthes-Calvé type "disease" of the hip. Autosomal recessive inheritance is proposed, although we cannot exclude the possibility of an X-linked recessive or an autosomal dominant condition with germinal mosaicism.     

Congenital eyelid ptosis and dental anomalies in the Francheschetti syndrome

The observation of an 11-years-old child is presented. He had bilateral congenital palpebral ptosis and multiple facial malformations, like maxillary and mandibular hypoplasia, dental malpositions, ogival palace, anomalies of the external ear, lesions determined by a latero-facial dechyscence (perforation 6, 7, 8). The affection was produced by a embryogenesis disturbance following the existence of two pathological genes. Their actions were overlapped during the 7--8 and 11 weeks of embryonic life, which caused damages in the maxillary and mandibular bones suture, which allow the formation of the inferior and middle stage of the face.     

Woody hands in a patient with pancreatic carcinoma: a variant of cancer-associated fasciitis--panniculitis syndrome

We report an elderly woman with rapidly progressive painless, woody induration of the hands. Mild diabetes mellitus was demonstrated. Skin biopsy features included broad fibrous bands extending deeply into subcutaneous fat, a mild mononuclear cell infiltrate, and post-thrombotic recanalization of a deep vessel in one specimen. The patient developed uncontrolled haematemesis and was demonstrated at laparotomy to have disseminated pancreatic carcinoma. The unusual clinical features and temporal relationship between the skin changes and the tumour suggest a paraneoplastic eruption. Which appears best classified as an example of cancer-associated fasciitis-panniculitis syndrome.     

Therapeutic importance of the diagnosis of Kallmann syndrome

Hyposmia with hypogonadotropic hypogonadism was diagnosed as Kallmann syndrome in a 24 years old dizygotic female twin. This syndrome indicates the importance of smell in the sexual development through the progenitor cells in the olfactory placode because luteinizing-hormone-releasing hormone (LHRH) secreting cells of hypothalamus arise from these cells. In addition, substitution therapy may be successful in the treatment of the lack of secondary sex traits and primary amenorrhoea as the presented case demonstrated.     

Bone marrow fibrosis and radiological changes of the long bones in children with acute megakaryocytic leukaemia

Using polymerase chain reaction, bottle-nosed dolphin (Tursiops truncatus) major histocompatibility complex (DoLA) class I alpha chain cDNA was cloned and sequenced. Predicted amino acid sequences of DoLA class I alpha chain have cystein residues for intradomain disulfide bond formation and N-linked glycosylation sites, suggesting that DoLA class I alpha chain molecules construct alpha 1, alpha 2, and alpha 3 domain structures. Similarity of DoLA class I alpha chain cDNA to land mammal MHC class I alpha chain cDNA was 90.4% in cattle, 90.2% in horse, 89.4% in sheep, and 87.8% in human. This investigation suggests that DoLA is closely related to land mammals.     

The electrophysiological mechanism of the long QT syndrome

There are several functions to modulate if action potential prolongation and early and late after depolarizations are expected to appear, namely: calcium/sodium channels gating modes, potassium channels rectification, 3Na+/1Ca+2 exchange function, left/to/right balance of the sympathetic innervation of the heart. Based upon chronological correspondence of electrophysiological events and surface ecg waves, heterogeneous prolonged repolarization and after depolarizations are two possible explanations for QT interval prolongation and dispersion in both acquired and congenital long QT syndromes. Pauses commonly trigger arrhythmias in acquired LQTS, and imbalanced sympathetic drive commonly triggers arrhythmias in the congenital type of the syndrome.     

Aneurysmal malformation of the vein of Galen in three patients: clinical and radiological follow-up

We studied three patients with aneurysmal malformations of the vein of Galen: all underwent embolisation followed by MRI and conventional angiography; two also underwent postembolisation magnetic resonance angiography (MRA). MRI was performed before treatment in two patients, MRA in only one, diagnosed prenatally. Two patients had normal appearances on follow-up MR studies and were completely cured by embolisation. However, the last patient, after two embolisations, despite the stabilisation of the clinical condition, underwent surgery and died. We think MRI is mandatory before endoarterial treatment, to assess the conditions of the brain. Angiography is mandatory only at the time of endovascular treatment, while MRA and MRI have a role in follow-up. Endoarterial embolisation remains the treatment of choice, and surgery is not advisable.     

Respiratory patterns during sleep in Down's syndrome:importance of central apnoeas

Obstructive sleep apnoea episodes have been reported repeatedly in Down's syndrome (DS) patients as a consequence of the presence of predisposing malformations or intercurrent pathology of the upper airways. There are no data on respiratory patterns of uncomplicated Down's syndrome subjects. In order to evaluate the eventual effects of central nervous system (CNS) impairment on respiration in DS, we studied the respiratory patterns during sleep of a group of 10 DS subjects, aged 8.6-32.2 y, without relevant upper airway pathology. In order to control the possible effects of sleep structure and mental retardation on the results obtained, we compared the findings in DS with those obtained from a group formed by subjects affected by fragile X syndrome (six males and one female, aged 10.0-15.42 y) another genetically determined type of mental retardation. Sleep structure was similar in both groups; however, DS subjects showed significantly higher indices of central sleep apnoea and of oxygen desaturation than fragile X patients (P < 0.005). As far as DS individuals were considered, a significant preponderance of central, as opposed to obstructive, sleep apnoeas was found (89.4% vs. 9.4%, respectively; 1.2% were mixed) which showed a significant age-related increase. Central respiratory pauses were mostly preceded by sighs, which occurred more frequently during sleep stages 1 and REM, and were often organized in long sequences of periodic-like breathing. During REM sleep, they were less frequently preceded by sighs and by body movements than during NREM sleep. Obstructive sleep apnoeas occurred more often during REM sleep and were more rarely preceded by sighs or by body movements. Both central and obstructive apnoeas induced significant oxygen desaturation in 50-69.6%. Sleep structure was not significantly modified by apnoeas and oxygen desaturation. We hypothesize that the increase in central sleep apnoeas is related to a dysfunction of the central respiratory control at a brainstem level in DS.     

Thallium-201 myocardial SPECT in Bland-White-Garland syndrome: two adult patients with inferoposterior perfusion defect

A myocardial 201TI SPECT examination was conducted both prior to and following surgery of two adult patients with an anomalous left coronary artery originating from the pulmonary artery (Bland-White-Garland syndrome). In this syndrome, the anterior wall is usually affected first. Preoperative examination demonstrated an inferoposterior perfusion defect. In both patients, the right coronary artery was markedly dilated, and a significant left-to-right shunt formation was observed. Both patients were diagnosed as possibly having coronary steal syndrome. A prolonged inadequate blood supply to the right coronary region may cause inferoposterior cardiomyopathy. In the postoperative examination, myocardial perfusion markedly improved in one patient whose preoperative SPECT showed redistribution in a delayed scan. Thallium-201 SPECT was therefore found to be useful in assessing both the preoperative and postoperative myocardial perfusion.