Should all patients with unexplained anaemia be screened for chronic lead poisoning?

Abstract

The global prevalence of lead poisoning is declining. However, the prevalence of lead poisoning in patients with either microcytic or normocytic anaemia is unknown. Blood samples from anaemic patients residing in south-east London without an obvious cause for anaemia had their blood lead concentration (BLC) analysed.A batch of 988 samples was analysed for BLC using atomic absorption spectroscopy. Median haemoglobin was 10.3 g/dL (range: 4.2–10.9) in females, 10.6 g/dL (range: 5.2–11.4) in males and 10.7 g/dL (range: 6.7–10.9) in children. Median BLC was 2.63 μg/dL (0.21–24.0 μg/dL; 95th centile 7.54 μg/dL). Fifteen samples (1.5%) had a BLC>10.0 μg/dL, five samples (1%)>15.0 μg/dL and one sample (0.1%)>20.0 μg/L. In the 106 children, median BLC was 2.34 μg/dL (0.5–14.5 μg/dL; 95th centile 6.12 μg/ dL). Only one child (14.5 μg/L) had a BLC>10.0 μg/dL. There was a poor correlation between haemoglobin and BLC (r2=0.08).Routine screening for lead poisoning cannot be justified in all patients with unexplained anaemia, unless there is a history or clinical features to suggest lead toxicity. Additionally, we have shown that in this former high-risk area for lead exposure, there is a low point prevalence of significant lead poisoning, even in an anaemic population.

Keywords

anaemia epidemiology lead poisoning screening

References

Philip AT , Gerson B . Lead poisoning. Incidence, etiology and toxicokinetics . Clin Lab Med 1994; 2: 422–444 .

Rabin R . Warnings unheeded: a history of child lead poisoning . Am J Publ Health 1989; 79: 1668–1674 .

CDC . Lead poisoning associated with ayurvedic medication – five states 2000–2003 . MMWR 2004; 53: 582–584 .

Delves HT , Diaper SJ , Oppert S , Prescott-Clarke P , Periam J , Dong W , et al. Blood lead concentrations in UK have fallen substantially since 1984 . BMJ 1996; 313: 883–884 .

Gogtay NJ , Bhatt HA , Dalvi SS , Kshiragar NA . The use and safety of non-allopathic Indian medicines . Drug Safety 2002; 25: 1005–1009 .

Thomas KJ , Coleman P , Nicholl JP . Trends in access to complementary or alternative medicines via primary care in England: 1995–2001 results of a follow-up national survey . Fam Pract 2003; 20: 575–577 .

Eisenberg D , Kessler RC , Foster C , Norlock FE , Calkins DR . Unconventional medicine in the US. Prevalence, costs and patterns of use . New Engl J Med 1993; 328: 246–252 .

Centers for Disease Control . Preventing lead poisoning in young children: a statement by the Centers for Disease Control. 1991.

Canfield RL , Henderson CR Jr , Cory-Slechta DA , Cox C , Jinko TA , Lanphear BP . Intellectual impairment in children with blood lead concentrations below 10 μg per deciliter . New Engl J Med 2003; 348: 1517–1526 .

10.

Bellinger DC , Stiles KM , Needleman HL . Low level lead exposure, intelligence and academic achievement: a long-term follow-up study . Paediatrics 1992; 90: 855–861 .

11.

Carton JA , Maradona JA , Arribas JM . Acute-subacute lead poisoning . Arch Intern Med 1987; 147: 697–703 .

12.

Gerson B . Lead . Clin Lab Med 1990; 10: 441–457 .

13.

Philip AT , Gerson B . Lead poisoning – effects and assay . Clin Lab Med 1994; 3: 651–671 .

14.

Graziano JH , Slavkovic V , Liu X , Factor-Litvak P , Todd A . Depressed serum erythropoietin in pregnant women with elevated blood lead . Arch Environ Health 1991; 46: 347–350 .

15.

Bradman A , Eskenazi B , Sutton P , Athanasoulis M , Goldman LR . Iron deficiency associated with higher blood lead in children living in contaminated environments . Environ Health Perspect 2001; 109: 1079–1084 .

16.

Wright RO , Tsaih SW , Schwartz J , Wright RJ , Hu H . Association between iron deficiency and blood lead level in a longitudinal analysis of children followed in an urban primary care clinic . J Pediatr 2003; 142: 9–14 .

17.

Wright RO , Shannon MW , Wright RJ , Hu H . Association between iron deficiency and low-level lead poisoning in an urban primary care setting . Am J Publ Health 1999; 89: 1049–1053 .

18.

Quinn MJ . Factors affecting blood lead concentrations in the UK: results of the EEC blood lead surveys 1979–1981 . Int J Epidemiol 1958; 14: 420–431 .

19.

Campagna D , Huel G , Hellier G , Girard F , Sahuquillo J , Fagot-Campagna A , Godin J , Blot P . Negative relationships between erythrocyte Ca-pump activity and lead levels in mothers and newborns . Life Sci 2000; 68: 203–215 .

20.

Graziano J , Slavkovich V , Liu X , Factor-Litvak P , Todd A . A prospective study of prenatal and childhood lead exposure and erythropoietin production . J Occup Environ Med 2004; 46: 924–929 .

21.

Fontana V , Baldi R , Franchini M , Gridelli P , Neri R , Palmieri F , et al. Adverse haematological outcome and environmental lead poisoning . J Expo Anal Environ Epidemiol 2004; 14: 188–193 .

22.

Grandjean P , Jensen BM , Sando SH , Jogensen PJ , Antonsen S . Delayed blood regeneration in lead exposure: an effect on reserve capacity . Am J Publ Health 1989; 79: 1385–1388 .

23.

Jacob B , Ritz B , Heinrich J , Hoelscher B , Wichmann HE . The effect of low-level blood lead on hematologic parameters in children . Environ Res 2000; 82: 150–159 .

24.

Poulos L , Qammaz S , Athanaselis S , Maravelias C , Koutselinis A . Statistically significant hematopoietic effects of low blood lead levels . Arch Environ Health 1986; 41: 384–386 .

25.

Rondo PHC , Carvalho MDFH , Souza MC , Moraes F . Lead, haemoglobin, zinc protoporphyrin and ferritin concentrations in children . Rev Saude Publ 2006; 40: 70–76 .

26.

Alabdullah H , Bareford D , Braithwaite R , Chipman K . Blood lead levels in iron-deficient and non iron deficient adults . Clin Lab Haematol 2005; 27: 105–109 .

27.

Ghisleni G , Spagnolo V , Roccabianca P , Scanziani E , Paltrinieri S , Lupo F , Ferretti E , Nageli F . Blood lead levels, clinico-pathological findings and erythrocyte metabolism in dogs from different habitats . Vet Hum Toxicol 2004; 46: 57–61 .

28.

Quinn MJ , Delves HT . The UK blood lead monitoring programme 1984–1987: results for 1986 . Hum Toxicol 1989; 8: 205–220 .

29.

Pirkle J , Brody DJ , Gunter EW , Kramer RA , Paschal DC , Flegal KM , et al. The decline in blood lead levels in the United States. The National Health and Nutrition Examination Surveys (NHANES) . JAMA 1994; 272: 284–291 .

30.

Centers for Disease Control and Prevention (CDC) . Blood lead levels United States, 1999–2002 . MMWR Morb Mortal Wkly Rep 2005; 54: 513–516 .

31.

Hwang YH , Ko Y , Chiang CD , Hsu SP , Lee YH , Yu CH , Chiou CH , Wang JD , Chuang HY . Transition of cord blood lead level, 1985–2002, in the Taipei area and its determinants after the cease of leaded gasoline use . Environ Res 2004; 96: 274–282 .

32.

Bitto A , Horvath A , Sarkany E . Monitoring of blood lead levels in Hungary . Cent Eur J Publ Health 1997; 5: 75–78 .