This study attempts to evaluate the adequacy of the erythropoietin (EPO) response in 42 anaemic patients with advanced human immunodeficiency virus (HIV) infection [30 with acquired immunodeficiency syndrome (AIDS) and 12 with AIDS-related conditions] by comparing their serum EPO levels with those found in a non-HIV reference population consisting of 36 patients with anaemia of chronic disorders (ACD) and 57 with iron deficiency anaemia (IDA). Although the average Hb concentration was similar in the three groups, the EPO level for HIV patients (mean +/- SEM, 64.3 +/- 7.7 mU/ml) did not differ significantly from that in ACD patients (45.3 +/- 8.3 mU/ml, P > 0.1), and both groups had a lower mean EPO level (P < 0.05 and P < 0.01 respectively) than IDA subjects (133.5 +/- 18.7 mU/ml). Thirteen HIV patients on zidovudine therapy showed similar mean Hb and EPO levels to those in the untreated patients. A significant inverse correlation between the log of serum EPO and the Hb values was observed in the three groups. However, this relationship was found to be stronger in IDA patients than in either HIV or ACD subjects (P < 0.001), with no difference between the two latter groups (P > 0.2). These data suggest that the EPO response is blunted in the anaemia associated with advanced HIV infection.

Serum erythropoietin (S-EPO) levels were measured in 50 patients with anaemia of chronic disorders (ACD), classified into three groups according to their aetiology: inflammatory (n = 20), infectious (n = 15) and neoplastic (n = 15). The inflammatory group showed a higher mean S-EPO level (mean value +/- SEM, 69 +/- 11 mU ml-1) than the neoplastic (43 +/- 5 mU ml-1; P less than 0.05) and infectious groups (27 +/- 4 mU ml-1; P less than 0.01). The S-EPO level in the inflammatory group also differed from that of 32 healthy controls (36 +/- 3 mU ml-1; P less than 0.05). Fourteen patients with added iron deficiency (12 subjects from the inflammatory group) showed the highest S-EPO concentration (72 +/- 17 mU ml-1). Conversely, S-EPO levels were lower in febrile subjects (12 patients with infection and five with malignancy) than in non-febrile patients (28 +/- 4 mU ml-1 vs. 55 +/- 7 mU ml-1; P less than 0.01). In the infectious group, the logarithm of S-EPO correlated directly with the haemoglobin and haematocrit values. We conclude that differences in S-EPO concentration in ACD may be further related to the patient's iron stores and temperature. A decrease in EPO production may contribute to the pathogenesis of ACD secondary to infection.

One hundred pregnant women, not anemic and not receiving iron or vitamin supplements, were chosen at random among the three trimesters of pregnancy to determine the incidence of unexpected iron, plasma folate and/or cobalamin deficiency, and the significance of fluctuating levels of their respective binding proteins. Pregnant females had a nonsignificant fall in serum iron and a fourfold decline in serum ferritin in the 3rd trimester compared with 1st trimester values. There was a steady decrease in plasma cobalamin and cobalophilin levels in every trimester but no difference in transcobalamin II values. Unsaturated cobalamin (UBBC) and unsaturated transcobalamin binding capacity (UTCBC) were lower in the 1st trimester fully recovering afterwards. Plasma folate levels were not lower, although there was a steady reduction in total and unsaturated folate binding capacity throughout pregnancy

The distribution of endogenous cobalamin among serum cobalamin-binding proteins was studied in 30 patients with active rheumatoid arthritis (RA) and 27 in clinical remission. The mean total serum cobalamin concentration (holo-transcobalamin I and II) was similar in both groups of patients, whereas mean apotranscobalamin II was significantly increased in patients with active RA. The clinical significance of this finding is not yet established but it might be a useful parameter for the evaluation of disease activity in RA.

In the suckling rat, neurotensin enhances the intestinal proliferative phenomenon but does not improve the course of medium-term postresection growth.