Plasmablastic lymphoma (PBL) is a type of large B-cell lymphoma recognized by the World Health Organization (WHO) in 2017 as belonging to a subgroup of lymphomas termed lymphoid neoplasms with plasmablastic differentiation. The other lymphoid neoplasms within this subgroup are: plasmablastic plasma cell lymphoma (or the plasmacytoma variant of this disease); primary effusion lymphoma that is Kaposis sarcoma-associated herpesvirus positive or Karposis sarcoma-associated Herpesvirus negative; anaplastic lymphoma kinase-positive large B-cell lymphoma; and human herpesvirus 8-positive diffuse large B-cell lymphoma, not otherwise specified. All of these lymphomas are malignancies of plasmablasts, i.e. B-cells that have differentiated into plasmablasts but because of their malignant nature: fail to differentiate further into mature plasma cells; proliferate excessively; and accumulate in and injure various tissues and organs.The lymphomas in the lymphoid neoplasms with plasmablastic differentiation sub-group that are not PBL have sometimes been incorrectly considered to be variants of PBL. Each of the lymphomas in this subgroup of malignancies have distinctive clinical, morphological, and abnormal gene features. However, key features of these lymphomas sometime overlap with other lymphomas including those that are in this sub-group. In consequence, correctly diagnosing these lymphomas has been challenging. Nonetheless, it is particularly important to diagnose them correctly because they can have very different prognoses and treatments than the lymphomas which they resemble.Plasmablastic lymphomas are aggressive and rare malignancies that usually respond poorly to chemotherapy and carry a very poor prognosis.
Benign neonatal sleep myoclonus (BNSM) is the occurrence of myoclonus (jerky movements) during sleep. It is not associated with seizures.BNSM occurs in the first few weeks of life, and usually resolves on its own within the first 3-4 months of life. It often worries parents because it can appear like seizures, but is not. Features that can help distinguish this condition from seizures include: The myoclonic movements only occur during sleep, when baby is woken up the myoclonic movements stop, normal EEG, normal neurological examination, normal developmental examination. The myoclonic jerks occur during non-REM sleep. References


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