Registro Italiano Malattia MYH9-Correlata
Newsletter - February 2010
Patients' enrolment
The number of patients enrolled in the Registry (www.registromyh9.org) is continuously growing. Since its institution in 2007, 578 patients have been evaluated for a suspected MYH9-RD and in 190 of them the diagnosis has been confirmed at the molecular level. Our case series now includes patients with 29 different mutations at 22 different positions of the MYH9 protein: 19 are missense, 8 nonsense or frameshift, one is an in frame deletion, and one is the first duplication responsible for this disorder. Due to the recent opening to foreign institutions, the Registry now comprises patients from 17 countries.
Published studies
During the last 12 months, 18 different groups published six papers based on the case series of the Registry. Three articles described novel MYH9 mutations (Eur J Haematol. 2009 Dec 11 - Platelets 2009;20:598-602 - Eur J Med Genet. 2009;52:191-4), one identified defective proplatelet formation as the pathogenetic mechanism of thrombocytopenia in MYH9-RD (Thromb Haemost. 2009;102:90-6) and another one identified some parameters of platelet size that can be useful in differentiating MYH9-RD, as well as other inherited thrombocytopenias, from ITP (J Thromb Haemost. 2009;7:2131-6). Finally, one paper measured the diagnostic power of immunofluorescence analysis of MYH9 protein distribution in neutrophils and concluded that this screening test is the best tool for diagnosing MYH9-RD (Thromb Haemost. 2010 Feb 19; 103).
Ongoing studies
The clinical trial on the thrombopoietin mimetic Eltrombopag in MYH9-RD is still enrolling patients and we foresee the close of the study before the end of 2010. Preliminary results are encouraging and we are confident that final analysis will show for the first time that increasing platelet count in inherited thrombocytopenias by a pill is an actual possibility.
The clinical study on cochlear implant in deaf patients is ongoing. Two cases received this treatment and both of them had fantastic results. Although the experience is still limited, cochlear implant seems to work very well in MYH9-RD and we suggest that this treatment have to be considered for all deaf patients. Since otolaryngologists of the IRCCS Policlinico San Matteo Foundation of Pavia are very experienced in this type of surgery, we suggest that you contact the Registry to arrange a consultation in case your deaf patients are willing to reach Pavia.
We are approaching the patients' number required for extending the genotype/phenotype correlations identified and described by the Registry in 2008 (Hum Mutat. 2008;29:409-17). We believe that the statistical analysis of 200 well characterized patients will greatly improve our ability to predict whether patients are at risk of deafness, cataracts and/or renal failure. However, to reach this goal we need the clinical and laboratory data of all new patients, as well as an updating on the clinical course of patients that have been enrolled in the past. Each centre will receive the list of the data we are waiting for in the next future.
Future prospective
Despite the present cutback of founding for scientific research in Italy, the Registry will continue to perform the screening test for MYH9-RD and the search for MYH9 mutations free of charge. Moreover, also sample shipping will be at expense of the Registry for Italian patients. So, the Registry will continue to be an important resource for all the people involved in clinical and/or research studies on MYH9-RD.
Since the Registry intends to be an open resource, do not hesitate to propose new studies and new activities.