Dyskeratosis congenita (DC) is a hereditary syndrome of bone marrow failure, which develops because of telomeres' defects and combines with cancer predisposition. Its classical clinical features are skin pigmentation, nail dystrophy, oral leukoplakia ("skin-mucosa triad"). The goal is to describe the algorithm of diagnosis, clinical specificities of DC and specific treatment for cases of DC in one family. The present report includes descriptions of diagnosis and treatment of family members diagnosed for the first time as having a DC. The report shows an importance of all diagnostic stages: from a medical history and clinical picture to an application of modern high-tech diagnostic methods (flow-FISH, NGS). The report underlines an importance of diagnosis of all family members for excluding an asymptomatic form after a case of DC has been already detected in that family. A high frequency of a toxicity and secondary neoplasia makes it necessary to realize an individual approach at treatment of each patient with DC (the earliest start of androgen treatment, prompt decision of implementation of allogenic hematopoietic stem cell transplantation). The knowledge of pathogenesis, clinical features and principles of diagnosis and therapy of this disease is relevant to pediatricians and hematologists.

Background Myelodysplastic syndromes (MDS) can present a challenge for clinicians. Multicolor flow cytometry (MFC) can aid in establishing a diagnosis. The aim of this study was to determine the optimal MFC approach for MDS. Methods The study included 102 MDS (39 low-grade MDS), 83 cytopenic patients without myeloid neoplastic disorders (control group), and 35 healthy donors. Bone marrow was analyzed using a six-color MFC. Analysis was conducted according to the "Ogata score," "Wells score," and the integrated flow cytometry (iFC) score. Results The respective sensitivity and specificity values were 77.5% and 90.4% for the Ogata score, 79.4% and 81.9% for the Wells score, and 87.3% and 87.6% for the iFC score. Specificity was not 100% due to deviations of MFC parameters in the control group. Patients with paroxysmal nocturnal hemoglobinuria (PNH) had higher levels of CD34(+)CD7(+)myeloid cells than donors. Aplastic anemia and PNH were characterized by a high proportion of CD56(+)cells among CD34(+)precursors and neutrophils. The proportion of MDS-related features increased with the progression of MDS. The highest number of CD34(+)blasts was found in MDS with excess blasts. MDS with isolated del(5q) was characterized by a high proportion of CD34(+)CD7(+)cells and low granularity of neutrophils. In 39 low-grade MDS, the sensitivities were 53.8%, 61.5%, and 71.8% for Ogata score, Wells score, and iFC, respectively. Conclusion The results support iFC as a useful diagnostic tool in MDS.

•Castleman disease is a rare cause of immune-mediated ataxia.•Cerebellar hemiatrophy can be found in patients with paraneoplastic cerebellar degeneration.•Detailed tumor screening should be performed in all patients with subacute cerebellar ataxia.