Lactate Dehydrogenase in the Diagnosis and Assessment of Response to Treatment of Megaloblastic Anaemia

Abstract

Gross elevation of the serum lactate dehydrogenase (S.L.D.) in megaloblastic anaemia was first reported by Hess and Gehm (1955) who found values from 5 to 21 times the upper limit of normal in 16 cases of pernicious anaemia. They also noted an inverse correlation between the serum enzyme activity and the peripheral red blood cell count. The rise in the S.L.D. has since been confirmed by Lührs and Negelein (1955), Cintrön‐Rivera, Acosta‐Martienzo and Diaz‐Rivera (1956), Zimmerman, West and Heller (1958), Heller, West and Zimmerman (1959), Gordin and Enari (1959), Levitan, Wasserman and Wróblewski (1959), Amelung (1960), Grönvail (1961), Elliott and Wilkinson (1963) and Goldfarb and Papp (1963), but there are conflicting reports concerning the relation between the degree of S.L.D. elevation and the severity of the anaemia.While Gordin and Enari (1959) reported that the S.L.D. activity correlated inversely with the serum vitamin B12 level, but not with either the blood haemoglobin concentration or the peripheral red cell count, in patients with pernicious anaemia or Diphyllobothrium latum infections, Levitan et al. (1959) found S.L.D. elevations in Addisonian anaemia only and not in megaloblastosis due to other causes. However, Amelung (1960) and Grönvall (1961) have suggested that the occurrence of extremely high S.L.D. activities might be diagnostic of megaloblastosis, and Fleming and Elliott (1964) have recently reported high levels of S.L.D. and of serum 2‐hydroxybutyrate dehydrogenase (S.H.B.D.) in folic acid‐deficient Nigerian patients with macrocytic anaemia of pregnancy. Similar elevation of the S.H.B.D. in pernicious anaemia had previously been reported by Elliott and Wilkinson (1963) who also observed a rise in the S.H.B.D./S.L.D. ratio during specific therapy.The present investigation was carried out to assess the reliability of S.L.D. and S.H.B.D. determinations in the diagnosis of megaloblastic anaemia and as indicators of the response to treatment. The enzyme levels have also been compared with the results of haematological investigations.