Biomedical subjects

H Quitmann

Publications and source records attributed to H Quitmann.

4 recordsLinked to original sources

PubMed2005

[Spinal manipulative therapy and cervical artery dissections].

Severe complications after cervical spine manipulation are rare. As experts for medical treatment errors, we received between July 2002 and February 2004 cases with serious complications in the central nervous system after manipulation. 5 vertebral artery dissections with subsequent brain infarction were registered. In all cases, the patients showed complete persisting remission of symptoms. In addition, a kinematic estimation model was developed to study the possible causes of vertebral artery damage. We were able to demonstrate that material extension is dependent on cervical rotation and the "free length" of the vertebral artery in the upper cervical spine.

Adult↗

PubMed2000

Very low platelet counts in post-transfusion purpura falsely diagnosed as heparin-induced thrombocytopenia. Report of four cases and review of literature.

Differential diagnosis between post-transfusion purpura (PTP) and heparin-induced thrombocytopenia (HIT) can be difficult in the initial stages of thrombocytopenia, as the early clinical presentations are often similar. Four patients are described who were suspected clinically of suffering from HIT. All four patients had recent blood transfusions and platelet alloantibodies, thus the diagnosis of PTP was made. One lethal gastrointestinal and one retroperitoneal hemorrhage developed in two of the four patients. Unusually, one patient was male and two different platelet alloantibodies were present in his serum; in another patient platelet alloantibodies and HIT-antibodies were detectable. To arrive at the right diagnosis as quickly as possible is vitally important since treatment, which has to be initiated promptly, is very different for the two syndromes. Thus, we suggest that in patients where HIT is suspected, additional information should be sought. If features consistent with PTP (such as a recent blood transfusion or a marked drop in platelet count to below 15 Gpt/L) are present, we recommend parallel testing for platelet alloantibodies to rule out PTP.

Acute Disease↗

PubMed1992

Megakaryocytopoiesis in bone marrow biopsies of patients with acquired immunodeficiency syndrome (AIDS). An immunohistochemical and morphometric evaluation with special emphasis on myelodysplastic features and precursor cells.

In 25 patients (22 males, 3 females--median age 39 years) with AIDS (CDC stages IV A-D) and no preceding myelotoxic therapy, morphometry and immunohistochemistry (CD 61-Y 2/51) was performed on trephine biopsies of the bone marrow to evaluate the megakaryocytic lineage. In comparison with megakaryocytes in the myelodysplastic syndromes (MDS) significant differences were evident. In AIDS this cell population revealed a size distribution within the normal range (control group) and no predominance of micromegakaryocytes characteristic for MDS. Furthermore, by determination of the form factors more irregular shapes of cell and nuclear perimeters could be shown. Finally, a not-evaluated number of precursors (promegakaryoblasts) was calculable. Particularly in those patients (n = 15) with AIDS-related severe thrombocytopenia the missing increase in the relative amount of promegakaryoblasts was conspicuous. This result was strikingly different from findings in idiopathic (autoimmune) thrombocytopenia and suggested an impairment of progenitor cell proliferation and differentiation in the acquired immunodeficiency syndrome. In conclusion, morphometry in combination with immunohistochemistry failed to establish characteristic myelodysplastic aspects of the megakaryocytic lineage in AIDS. For this reason, bone marrow lesions in this disorder should be properly termed HIV-myelopathy and not myelodysplasia.

Acquired Immunodeficiency Syndrome↗

PubMed1991

Dysmegakaryopoiesis in myelodysplastic syndromes (MDS): an immunomorphometric study of bone marrow trephine biopsy specimens.

An immunohistochemical and morphometric analysis was performed on trephine biopsy specimens of the bone marrow in 40 patients (23 men and 17 women, mean age 62 years) with different subtypes of myelodysplastic syndromes (MDS) to determine dysmegakaryopoiesis, but particularly precursor cells--that is, pro- and megakaryoblasts. In 31 of the 40 patients the numbers of megakaryocytes were increased which was associated with a predominance of smaller cell forms (micromegakaryocytes). Compared with periodic acid Schiff, immunostaining with a formalin resistant monoclonal antibody against glycoprotein IIIa (Y2/51(CD61) showed a clinically important proportion of immature elements. These could be designated pro- and megakaryoblasts by taking morphometric measurements on smears and bone marrow sections. There was a relevant increase in the number of promegakaryoblasts in 32 patients, consistent with uncontrolled expansion of the precursor pool. Seventeen repeated bone marrow biopsy specimens taken after chemotherapy largely showed a decrease in the numbers of megakaryocytes including the precursor cell population. Moreover, morphometric evaluation disclosed that micromegakaryocytes in MDS differ significantly from those in chronic myeloid leukaemia (CML) due to distinctive nuclear features and a disturbed nuclear:cytoplasmic ratio. These changes generate a more pleomorphic or atypical appearance of this cell population in MDS, compared with micromegakaryocytes in CML. It is concluded that the disproportionate increase in megakaryocyte precursors and the grossly abnormal aspects of micromegakaryocytes in MDS are characteristics of the severe defect involving haematopoiesis in this disorder.

Adult↗