Central diabetes insipidus: an unusual complication in a child with juvenile myelomonocytic leukemia and monosomy 7

Venetoclax/decitabine for a pediatric patient with chronic myelomonocytic leukemia

Chronic myelomonocytic leukemia (CMML) is a myelodysplastic syndrome (MDS)/myeloproliferative disorder most commonly seen in the elderly. We describe an adolescent with monosomy 7 CMML presenting as central diabetes insipidus (DI), who was treated with venetoclax and decitabine as a bridge to hematopoietic stem cell transplantation (HSCT). Central DI is a rare manifestation of monosomy 7-associated MDS including CMML, itself a rare manifestation of GATA2 deficiency, particularly in children. Venetoclax/decitabine was effective for treatment of CMML as a bridge to HSCT.

'If there were water we should stop and drink': neurofibromatosis presenting with diabetes insipidus

A 58-year-old right-handed woman presented to our institution with a 1-month history of polydipsia and polyuria. She had a remote history of neurofibroma excision by dermatology and, on examination, was noted to meet the clinical diagnostic criteria for neurofibromatosis type 1. Laboratory investigations revealed hypernatraemia and elevated serum osmolality, accompanied by reduced urinary osmolality. A subsequent water deprivation test confirmed central diabetes insipidus, which responded to treatment with desmopressin. MRI of the brain showed pituitary enlargement, which raised the possibility of an underlying pituitary adenoma or, alternatively, lymphocytic hypophysitis. Both conditions have rarely been described in neurofibromatosis.

Cancer cytogenetics: methodology revisited

The Philadelphia chromosome was the first genetic abnormality discovered in cancer (in 1960), and it was found to be consistently associated with CML. The description of the Philadelphia chromosome ushered in a new era in the field of cancer cytogenetics. Accumulating genetic data have been shown to be intimately associated with the diagnosis and prognosis of neoplasms; thus, karyotyping is now considered a mandatory investigation for all newly diagnosed leukemias. The development of FISH in the 1980s overcame many of the drawbacks of assessing the genetic alterations in cancer cells by karyotyping. Karyotyping of cancer cells remains the gold standard since it provides a global analysis of the abnormalities in the entire genome of a single cell. However, subsequent methodological advances in molecular cytogenetics based on the principle of FISH that were initiated in the early 1990s have greatly enhanced the efficiency and accuracy of karyotype analysis by marrying conventional cytogenetics with molecular technologies. In this review, the development, current utilization, and technical pitfalls of both the conventional and molecular cytogenetics approaches used for cancer diagnosis over the past five decades will be discussed.