Perry Syndrome

Disease characteristics. Perry syndrome is characterized by parkinsonism, hypoventilation, depression, and weight loss. The mean age at onset is 48 years; the mean disease duration is five years. Parkinsonism and psychiatric changes (depression, apathy, character changes, and withdrawal) tend to occur early; severe weight loss and hypoventilation manifest later. Diagnosis/testing. The diagnosis is based on clinical findings and molecular genetic testing of DCTN1, the only gene known to be associated with Perry syndrome. Management. Treatment of manifestations: Dopaminergic therapy (particularly levodopa/carbidopa) should be considered in all individuals with significant parkinsonism. Although response to levodopa is often poor, some individuals may have long-term benefit. Noninvasive or invasive ventilation support may improve quality of life and prolong life expectancy. Those patients with psychiatric manifestations may benefit from antidepressants and psychiatric care. Weight loss is managed with appropriate dietary changes. Surveillance: routine evaluation of weight and calorie intake, respiratory function (particularly at night or during sleep), strength; and mood. Agents/circumstances to avoid: Central respiratory depressants (e.g., benzodiazepines, alcohol). Genetic counseling. Perry syndrome is inherited in an autosomal dominant manner. The proportion of cases attributed to de novo mutations is unknown. Each child of an individual with Perry syndrome has a 50% chance of inheriting the mutation. No laboratories offering molecular genetic testing for prenatal diagnosis are listed in the GeneTests Laboratory Directory; however, prenatal testing may be available through laboratories offering custom prenatal testing for families in which the disease-causing mutation has been identified.

Molecular pathology of colorectal cancer.

Colorectal cancer (CRC) is one of the most intensively studied cancer types, partly because of its high prevalence but also because of the existence of its precursor lesions, tubular or villous adenomas, and more recently (sessile) serrated adenomas, which can be detected endoscopically and removed. The morphological steps in the adenoma-carcinoma sequence have been elucidated at a molecular level, which has been facilitated by identification of the genes responsible for familial intestinal cancer. However, apart from early detection of familial forms of CRC and its use in genetic counseling, until recently such detailed molecular knowledge has had little impact on clinical management of the disease. This has dramatically changed in the last decade. With drugs specifically targeting the epidermal growth factor receptor (EGFR) having been shown effective in CRC, mechanisms responsible for resistance have been explored. The finding that KRAS mutated cancers do not respond to anti-EGFR treatment has had a profound impact on clinical management and on molecular diagnostics of CRC. Additional genetic tests for mutations in NRAS, BRAF and PIK3CA contribute to determining who to treat, and others will follow. New therapies effective in patients with advanced CRC are under investigation. Remaining burning questions for optimal management are which patients will relapse after resection of the primary tumor and which patients will respond to the standard 5FU-oxaliplatin adjuvant treatment regimen. Predictive tests to address these issues are eagerly awaited. New classifications of CRC, based on molecular parameters, are emerging, and we will be confronted with new subtypes of CRC, for which the definition is based on combinations of gene expression patterns, chromosomal alterations, gene mutations and epigenetic characteristics. This will be instrumental in designing new approaches for therapy but will also be translated into molecular diagnostics. Both will contribute to improved clinical management of CRC.

Nouveautés dans l'ostéogenèse imparfaite: de la recherche à la prise en charge multidisciplinaire [News in osteogenesis imperfecta: from research to clinical management]

Osteogenesis imperfecta (OI) is a rare genetic disease. Today we are able to propose an adapted and efficient management to the patients with this rare disorder (and their families) thanks to a strong collaboration of clinicians and researchers. Recent knowledge regarding the genetics of OI permits an accurate diagnosis of the specific type of OI and its own molecular mechanism, a genetic counseling for family planning and prenatal diagnosis, and in addition more targeted therapeutic options. A specific support with re-education for patients with OI is necessary and efficient. To optimize patient care, a multidisciplinary consultation is proposed at the CHUV, moreover a web site is available for patients, families and therapists: www.infomaladiesrares.ch