A rare case of near-haploid acute lymphoblastic leukemia.

Near-haploid acute lymphoblastic leukemia is seen in <1% of cases and carries an unfavorable prognosis. We report a case in an 18-year old male. He presented with two abnormal clones, one with 27-28 and one with 54-56 chromosomes. Near-haploidy (27-28) carries a poor prognosis and hyperdiploidy (>50) has a good prognosis. The correct diagnosis was critical for this patient's prognosis and treatment. The patient achieved remission after a bone marrow transplant from a 10/10 HLA matched sibling donor. He relapsed six months later and expired seven months later. This case illustrates the need for careful standard and molecular cytogenetic analysis for accurate diagnosis and treatment for this rare type of ALL.

Cytogenetic evaluation: a primer for pediatric nurse practitioners.

Patients with genetic disorders require specific types of cytogenetic testing for accurate diagnosis and prognosis followed by prompt treatment. This primer will serve as a guide for pediatric nurse practitioners on the use of various cytogenetic testing for the diagnosis of genetic disorders. Knowledge of the latest cytogenetic technologies will facilitate diagnosis and counseling related to genetic abnormalities such as inherited disorders, mental retardation, developmental delay, and autism. This reference will enable pediatric nurse practitioners to help identify patients with various inherited genetic disorders and provide subsequent monitoring and treatment.

Ovotesticular disorder of sexual development (true hermaphroditism).

OBJECTIVES: To determine the mechanism for the 46,XX/46,XY karyotype observed in a patient with an ovotesticular disorder of sexual development (ie, true hermaphroditism). METHODS: Cytogenetic, molecular cytogenetic, and molecular DNA analyses were performed on the blood, skin, and left and right gonadal tissue from 2 surgical procedures. The results of these studies were used to determine whether the ovotesticular disorder of sexual development resulted from mosaicism or tetragametic chimerism. RESULTS: Cytogenetic and molecular analyses revealed a mixture of 46,XX and 46,XY cells in most tissues. DNA analysis from the gonadal tissues from surgeries 1 and 2 was performed. Highly polymorphic loci from 12 different chromosomes were examined for the presence of > or = 1 paternal or maternal alleles. Three loci were highly informative: D14S544 (14q32.2), DS14S583 (14q21.3), and SE33 (6q14). Each demonstrated the presence of 2 paternal and 2 maternal alleles, indicating that the ovotesticular disorder of sexual development resulted from tetragametic chimerism. CONCLUSIONS: Based on the findings of the cytogenetic, molecular cytogenetic, and DNA analyses of the polymorphic markers from several different loci, it was confirmed that the patient had tetragametic chimerism. This case has assisted in increasing our knowledge of the possible mechanisms causing this rare and complex disorder.