7/27/2019 Acquired Methemoglobinemia

1/2

Ninety-five (63%) mothers qualified as havingheavy traffic exposure and 55 (37%) as light trafficexposure. Among the exposed group, 11.6% had leadpoisoning compared with 7.3% of unexposed group.A positive association was found, between living nearheavy traffic and lead poisoning, OR 1.6, however,this association was not statistically significant with aP-value of 0.3. Likewise other exposure risk factors,e.g. use of tap water for cooking and drinking, andliving in a painted house also showed a positiveassociation with OR 1.4 and 1.4, respectively,but this association was not statistically significant(P-value 0.4 and 0.5, respectively).

Cosmetics (black eye liner) was used by 58.7% of allmothers, however, there was no association betweenlead poisoning and use of cosmetics, OR 1.

Discussion

It is well recognized that cord blood lead levelscorrelate closely with maternal blood lead levels andthat this can be used as a community-screeningprocedure [7].

This study found that the overall prevalence of leadpoisoning (defined as blood lead level 10mg/dl) incord blood among newborns is 10%. Given that, thereis no naturally occurring level of lead in the humanbody, and that lead is unsafe at any level, therefore, aprevalence of 10% is of public health importance.Evidence is now emerging that, levels even below10mg/dl can cause neurological damage; although alevel of 10mg/dl is still an acceptable level of safety [8].

The correlation of cord blood lead level has beenpreviously reported to be 70% of maternal level [7].Thus, the 10% prevalence of lead poisoning in thecord blood would reflect about the same level of

prevalence among mothers; and be considered torepresent the prevalence of lead poisoning in thegeneral population of Dar es Salaam where thesemothers come from.

In this study, confounding factors such as severeanaemia, EPH gestosis, severe malnutrition andmultiple pregnancies were considered. The effects ofthese potential confounders as effect modifiers werecarefully studied. There was no correlation betweenthese potential confounders and low birth weight orprematurity.

Although this study did not find significantcorrelations with recognized risk factors, it clearly

indicates that there is about 10% prevalence. Thisreport therefore augments the available reports inTanzania, giving evidence that lead poisoning isindeed a problem [9].

Funding

Ministry of Health and Social Welfare.

MARY M. AZAYO, KARIM MANJI, andFESTUS KALOKOLA

Department of Paediatrics and Child Health,Muhimbili University of Health and Allied Sciences

(MUHAS), Dar-es-Salaam, Tanzania

doi:10.1093/tropej/fmn085Advance Access Published on 4 October 2008

References

1. Nriagu JO, Blackson M, Ocran K. Childhood leadpoisoning in Africa, a growing public health problem.Sci Total Environ 1996;181:100.

2. Mathee A, Von Schirrnding YE, Levin J, Ismail A.A survey of blood level among Johannesburg schoolchildren. Environ Res 2002;90:1814.

3. StatementWorld Bank Regional Conference on thephase out of leaded gasoline in sub-Saharan Africa,Dakar, Senegal, 2628 June 2001.

4. Yen C, Shen X, Ao L. Lead exposure in umbilical cordblood and its related factors. Zhonghua Yu Fang YiXue Za Zhi 1997;31:912.

5. Lead Toxicity on reproductive health, fetal develop-ment, and breast milk, chapter 13, 2002: The Wisconsinchildhood lead poisoning prevention and control.http://dhs.wisconsin.gov/lead/doc/chapter13Preg&Breast.pdf(8 July 2008, date last accessed)

6. Furman A, Laleli M. Maternal and umbilical cordblood lead levels: an Istambul study. Arch EnvironHealth 2001;56:268.

7. Bughurst PA, Robertson RK, Oldfield BM,et al. Leadin placentae, membranes and umbilical cord in rela-tion to pregnancy outcome. Environ Health Persp1991;90:31520.

8. Carbone R, Laforgia N, Crollo E, et al. Blood leadlevels during pregnancy in the newborn period. Study ofthe population of Bari. Ann Ist Supper Sanita

1998;34:1179.9. Mashimba ENM, Kalima J, Mtega S. The use of

laboratory analytical data for health and safety. Apaper presented at the 5th environmental and theoreti-cal chemistry workshop in Africa, University of Dar esSalaam, December 2003.

Correspondence: Prof. Karim Manji, Department ofPediatrics and Child Health, MUHAS, P.O. Box 65001,Dar-es-Salaam, Tanzania. Tel: 255754 350630,Fax: 255 222153114. E-mail .

Acquired Methemoglobinemia Due to ContaminatedColours: A Preventable Disaster

To celebrate the beginning of spring in India, atraditional Hindu colour festival called Holi iscelebrated by people by throwing coloured powdersor spraying coloured water on each other. On 7

RESEARCH LETTERS

The Author [2009]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org 139

7/27/2019 Acquired Methemoglobinemia

2/2

March 2004 on Holi day, 10 children were admittedto our ward in quick succession, over a 45 h period,with complaints of breathlessness and drowsinesswhich had developed within 12 h of playing withcolours bought from a local vendor. The age of thechildren (five were boys) ranged from 4 to13 years(mean age 9.2 years).

The first patient to be admitted was a 4-year-old

boy. On clinical examination, he had shallow andirregular respiration, central cyanosis and was deeplyunconscious. He was intubated and ventilated. Hisblood appeared chocolate brown in colour. Hisarterial blood gas analysis revealed an increasedlevel of methemoglobin (60.9%) with normal partialpressure of oxygen (PaO2) and oxygen saturationlevels. A diagnosis of acquired methemoglobinemiadue to contaminated colours was made. He was givena thorough stomach and skin wash, nasal oxygen,supportive intravenous fluids and intravenousmethylene blue (1mg/kg over 10min) [1, 2] Ascyanosis persisted the methylene blue dose wasrepeated after half an hour. After another 3 h, thepatient regained consciousness, had normal respira-tion and was extubated. His methemoglobin levelhad normalized to 0.9%.

The other nine children were also breathless,drowsy and had central cyanosis. However, theydid not require ventilatory support. Methemoglobinlevel was raised in all of them ranging from 18% to48% with normal PaO2 and oxygen saturation levels.All of them were treated similarly. All 10 childrenrecovered fully and were discharged the next day.

This year, also during the festival of Holi (March2008), two children aged 8 years were admitted to ourhospital with breathlessness and drowsiness after

exposure to contaminated colours. Investigationsconfirmed the diagnosis of acquired methemoglobi-nemia and both children were successfully managedby us.

Methemoglobin is an altered state of hemoglobinwhereby the ferrous form of iron is oxidized to theferric state, making the heme moiety incapable ofcarrying oxygen [2]. Methemoglobinemia causesserious tissue hypoxia when the amount of reducedhemoglobin exceeds 5 g/dl [2]. Nitrites are potentoxidant agents of ferrohemoglobin [2]. Acquired

methemoglobinemia has been reported to developin children after exposure to oxidant drugs such asdapsone, local anesthetic agents; high-nitrate foodssuch as spinach, carrots, silver beets consumed ashomemade purees; as well as acute nitrite toxicityresulting from accidental exposure to aniline dyes,colouring compounds or cleaning solutions [2].However, an extensive PubMed search did notreveal a single case report of acquired methemoglo-binemia due to exposure to contaminated coloursused during Holi festival.

We suspect that the colours used in the Holifestival were contaminated with aniline dyes whichare known to cause acquired methemoglobinemia inIndian industrial workers as an occupational hazard[3]. In bringing the attention of pediatricians to thisrare cause of acquired methemoglobinemia, we hopethat it will result in its prompt treatment and possibleprevention.

ANUPAMA MAUSKAR, SUNIL K ARANDE, andMADHURI KULKARNI

Department of Paediatrics, Lokmanya TilakMunicipal Medical College and General Hospital,Sion, Mumbai (Bombay) 400 022, Maharashtra,

India

doi:10.1093/tropej/fmn119Advance Access Published on 21 January 2009

References

1. Clifton J 2nd, Leikin JB. Methylene blue. Am J Ther2003;10:28991.

2. Dahshan A, Donovan GK. Severe methemoglobinemiacomplicating topical benzocaine use during endoscopy

in a toddler: a case report and review of the literature.Pediatrics 2006;117:e8069.

3. Dewan A, Patel A, Saiyed H. Acute methemoglobine-mia a common occupational hazard in an industrialcity in western India. J Occup Health 2001;43:16871.

Correspondence: Dr Anupama Mauskar, AssociateProfessor of Paediatrics, Department of Paediatrics,Lokmanya Tilak Municipal Medical College and GeneralHospital, Sion, Mumbai (Bombay) 400 022, India.Email .

RESEARCH LETTERS

140 Journal of Tropical Pediatrics Vol. 55, No. 2