Effect of isoniazid, a haem inhibitor, on globin chain synthesis in reticulocytes from non-thalassaemic and beta thalassaemic subjects

The effect of isonicotinic acid hydrazide (INH), a potent haem inhibitor, on globin chain synthesis was studied in reticulocytes from the following groups of patients: four non-thalassaemic patients (group i); five beta thalassaemia heterozygotes (group ii); three Hb S/beta thalassaemia heterozygotes (group iii); and two additional patients--one with homozygous beta thalassaemia and the other with thalassaemia intermedia (group iv). This was done to determine whether haem inhibitors depress alpha globin chain synthesis. The progressive increase of INH concentration (10-40 mmol l-1) in reticulocytes from a beta thalassaemia heterozygote resulted in a remarkable decrease of the alpha and beta chain synthesis, ranging from 80% to 97% and from 74% to 96% of control values, respectively, and in a gradual drop of alpha:beta ratio from 1.87 to 1.38. Furthermore, in the samples incubated with 40 mmol l-1 INH, a pronounced inhibition of globin chain synthesis 77 (19%) for alpha chain and 67 (27%) for beta or beta S chain) and a substantial drop of the alpha:beta or beta S ratio in samples with INH (median 1.16) compared with that in samples without INH (median 1.70) were observed. The inhibitory effect of INH was significantly or completely corrected by adding exogenous haem. It is suggested that haem inhibition and the resulting preferential diminution of alpha chain synthesis could provide a new approach to the treatment of homozygous beta thalassaemia with an excess of detrimental free alpha chain in erythroid cells.

Monoclonal gammopathy in chronic myeloproliferative disorders

The incidence of monoclonal gammopathy in 61 patients with chronic myeloproliferative disorders (CMPD) was studied. The distribution of patients among the CMPD subgroups was: chronic myelocytic leukemia, 24 patients; myelofibrosis, 11; polycythemia vera, 15; essential thrombocythemia, 7; unclassified MPD, 4 patients. Monoclonal gammopathy was found in 5 patients (8.2%). Two of these patients (1 IgA/k and 1 IgM/k) had myelofibrosis and 3 (2 IgG/k and 1 IgG/lambda) polycythemia vera. The presence of monoclonal gammopathy indicates an involvement of the lymphoplasmatic system in CMPD.

Myelodysplastic syndromes: analysis of 131 cases according to the FAB classification

The clinical and haematological findings in 131 patients with myelodysplastic syndromes (MDS), none of which had previously received chemotherapy or radiotherapy, classified according to the FAB criteria, were analysed. The distribution among the 5 subgroups was: RA 31 patients, RAS 19, RAEB 23, CMML 29 and RAEBT 29 patients. There were difficulties in the classification of 24 patients. These included, first, 8 cases with myeloid hyperplasia of the bone marrow (BM) but without monocytosis or excess of blasts of the BM. They were classified as RA. Second, 8 cases with sideroblastosis but with monocytosis or excess of blasts of the BM were classified 3 as RAEB, 2 as CMML and 3 as RAEBT. Finally, 8 cases with absolute monocytosis and BM blasts 15-30% were classified as CMML. 37 of 82 dead patients (45.1%) had transformed to acute non-lymphoblastic leukaemia (ANLL). The incidence of evolution to ANLL was low for RA and RAS (6.30% and 12.5% respectively), while it was 37.5% for RAEB, 57.1% for CMML and 77.2% for RAEBT. The median survival for each subgroup was: RA 18 months; RAS 25; RAEB 13; CMML 14 and RAEBT 10 months. It is concluded that the FAB classification with some modifications recognises group of MDS with different prognosis.

Myeloproliferative disorder during the course of multiple myeloma

A patient with multiple myeloma who developed a myeloproliferative disorder 6 years after initial diagnosis is described. The 2 disorders coexisted for 3 years. Possible explanations for this occurrence are discussed.

Primary gastric lymphoma--the experience of a general hospital

We analysed 29 consecutive cases of primary gastric lymphoma (20 men and 9 women) treated in our unit between January 1977 and May 1983. Median age was 55 years. Abdominal pain and weight loss were the main presenting symptoms while there was no palpable disease in the majority of cases. Upper gastrointestinal radiology was abnormal, but not diagnostic, in all cases. Endoscopy with multiple biopsies was performed in 22 cases; carcinoma was diagnosed in 11, lymphoma in 8 while no diagnosis was made in 3 cases. Twenty six patients underwent laparotomy. Gastrectomy was performed in twenty while the tumour was unresectable in six. Histology was reported as diffuse in 28 cases (16 histiocytic, 8 lymphocytic and 4 mixed) and nodular (lymphocytic) in one. All our patients received multichemotherapy. Complete remission after 6 courses was documented in 18 patients (62%). Neither perforation nor gastrointestinal bleeding was a problem in our series. Eighty four per cent complete responders are predicted to be alive at 4 years. Advanced stage (II2B and IV) and tumour size greater than 10 cm adversely influenced survival. We suggest that in limited primary gastric lymphoma an attempt at 'curative' surgery combined with multichemotherapy currently gives very promising results.

Immune abnormalities in myelodysplastic syndromes

The immune states of 52 patients with myelodysplastic syndromes classified according to the FAB criteria were studied. Serum electrophoresis and immunoelectrophoresis, direct Coombs test, and tests for organ and non-organ specific antibodies were performed. Twenty six patients had immunoglobulin abnormalities: six (11.5%) had monoclonal gammopathy; 17 (32.6%) had polyclonal increases in serum immunoglobulin; while in three (5.8%) immunoglobulin concentrations were decreased. The distribution of immunoglobulin abnormalities among the five myelodysplastic syndrome subtypes was fairly uniform. Results of direct Coombs test were negative in all cases. Organ specific antibodies were not detected in any of the patients tested, although two patients were found positive for antinuclear antibodies. The presence of immunoglobulin abnormalities indicates an involvement of the lymphoplasmatic system in myelodysplastic syndromes.

Refractory anaemia with excess of blasts terminating as Ph1 negative chronic myeloid leukaemia

A case of refractory anaemia with excess of blasts ( RAEB ) terminating with clinical and haematological picture of Ph1 negative chronic myeloid leukaemia (CML) is reported. It is suggested that the same abnormal clone of cells is responsible for the initial picture of the RAEB and the terminal CML picture.

Correlation of haematological, electron microscopic and cytogenetic findings in 20 patients with preleukaemia

A combined haematological, ultrastructural and chromosomal study was made in 20 patients with preleukaemia. There was evidence of specific correlations between (a) Hb F levels and pancytopenia or profound anaemia, (b) chromosomal and electron microscopic findings and (c) thrombocytosis and ringed sideroblasts. The above findings might be of importance in identifying subgroups of preleukaemic patients with different prognosis.

'Prolymphocytoid' cells in chronic lymphocytic leukaemia and their prognostic significance

The morphology of lymphocytes in blood and bone marrow smears from 103 patients with chronic lymphocytic leukaemia (CLL) was studied. Special attention was paid to the finding of immature cells with the morphological features of prolymphocytes (prolymphocytoid cells -PLC). Subsequently the prognostic significance of these cells was examined. It was found that in 85 cases no PLC were found (Group I); in 8 cases the percentage was less than or equal to 10% (Group II) and in 10 cases the PLC were greater than 10% (Group III). The cases with PLC, especially in group III, fell in advanced stages of the disease (III-IV) and presented with increased lymphocytosis. In 8 patients of group III, who were followed till death, the disease became refractory to any treatment and the survival was short. We suggest that 'prolymphocytoid' transformation is a bad prognostic sign in CLL.

Myelodysplastic syndrome. Clinical and prognostic significance of monocyte count, degree of blastic infiltration, and ring sideroblasts

In a retrospective study 37 patient who fitted into the clinical spectrum of myelodysplastic syndrome were reviewed. Special attention was paid to the influence of monocyte count, degree of blastic infiltration and ring sideroblasts and on the clinical presentation and the course of the disease. Monocyte count clearly distinguishes between two groups of patients with different haematological profile and clinical course. The patients with monocytosis frequently changed to acute myeloid leukaemia and had shorter survival rates compared with those without monocytosis. The degree of blastic infiltration does not affect the haematological presentation and the frequency of acute leukaemia evolution. However, increased blastic infiltration is associated with shorter survival. Patients with ringed sideroblasts presented with profound anaemia but the clinical course of the disease did not differ from the remainder.

Analysis of 75 cases of acute myeloid leukaemia classified according to the FAB classification

75 cases of acute myeloid leukaemia were retrospectively classified according to the French-American-British (FAB) classification. It was found that: (1) the proposed classification was easily applicable and reproducible; (2) M2 subtype was the most frequent (48%); (3) splenomegaly was absent in M1 subtype, and (4) in M2 subtype, a considerable number of cases presented with normal neutrophil and platelet counts.