Reduction of excessive haematocrit levels in patients with polycythaemia due to hypoxic lung disesae by phenylhydrazine hydrochloride and pyrimethamine

Abstract

Summary A series of fourteen patients with polycythaemia due to hypoxic lung disease has been treated with a combination of phenylhydrazine hydrochloride and pyrimethamine to reduce the haematocrit level, with doses usually of up to 100 mg/day (and rarely up to 150 mg/day) of the former and never more than 12·5 mg/day of the latter. Successful reduction of the haematocrit level was achieved in every case without any significant thrombocytopenia, the lowest level ever occurring being 100,000 platelets/mm3 in two patients. All the patients were improved symptomatically.

Exchange Transfusion with Dextran 40 in Polycythaemia Secondary to Hypoxic Lung Disease

“…with symptomatic benefit but ordinarily necessitates a hospital stay of about six weeks (Chamberlain and Millard, 1963). Pyrimethamine with dapsone or phenylhydrazine has also been used and produced symptomatic improvement, but these drugs carry the risk of thrombocytopenia and overcorrection of the polycythaemia (Pengelly, 1966(Pengelly, , 1969.…”

Clinical features of polycythaemic patients with chronic obstructive non-specific lung disease

“…The higher TF figures which Burrows et al (1964 and1966) noted in their bronchitic subjects compared to those with more emphysematous features may be attributable partly to the higher haemoglobin levels which were observed in the former. Roughton and Forster (1957) showed that TF can be related to haemoglobin concentration.…”

“…They were therefore characterized by many of the features which Burrows andhis colleagues (1964 and1966) associated with obstructive bronchitis. In contrast, the non-polycythaemic group had a much higher incidence of emphysema with little evidence of cardiac involvement.…”

“…The justification for doing this is based on evidence which suggests that the development of polycythaemia can produce a poor prognosis in this condition (Mitchell, Webb, and Filley, 1964) due to the development of pulmonary hypertension and high blood viscosity producing heart failure and further hypoxia (Harvey et al, 1951;Renzetti, McClement, and Litt, 1966;Segel and Bishop, 1966;Dintenfass and Read, 1968;Agarwal, Paltoo, and Palmer, 1970). Furthermore, encouraging results have been obtained by those who have reduced the level of polycythaemia by, for example, using continuous oxygen (Chamberlain and Millard, 1963), venesection (Massaro and Katz, 1965;Rakita, Gillespie, and Sancetta, 1965), haemolytic drugs combined with marrow suppressants (Pengelly, 1966 and1969), and, more recently, exchange transfusion with Dextran 40 (Harrison, Gregory, Clark, and Scott, 1971). However, the efficacies of these measures need further assessment, as all these observations were made on relatively few patients without matched controls.…”

The Effects of Therapeutic Decrease in Packed Cell Volume on the Responses to Exercise of Patients with Polycythaemia Secondary to Lung Disease

“…polycythaemic patients (Chamberlain & Millard, 1963;Pengelly, 1966Pengelly, , 1969Gregory, 1971a;Harrison et al, 1971), but previous studies have failed to demonstrate important objective improvement (Segel & Bishop, 1966). In the present paper we report the results of progressive exercise tests and circulatory studies in a group of patients with lung disease and secondary polycythaemia before and after decrease in PCV following exchange transfusion with Dextran 40 (Gregory, 1971b).…”