رد: مستوى معدن الزنك يف مصل دماء األطفال املصابني بإسهال دموي أو
مائي حاد

Re: Serum Zinc Concentrations in Children with Acute
Bloody and Watery Diarrhoea

Sir,

I have two comments regarding the interesting study by Mahyar et al. published in the SQUMJ November
2015 issue.1 Firstly, apart from the two limitations addressed by the authors—failure to estimate serum zinc
concentrations after patients had completed their course of treatment and the small sample size—I believe that
there is another important limitation to this study. Giardiasis is highly prevalent in developing countries.2 It is
commonly linked to chronic diarrhoea and malabsorption; available data indicate that giardiasis is the aetiological
agent in 7.0% of childhood cases of acute diarrhoea.3 In Iran, paediatric giardiasis still represents a substantial health
threat, with an estimated prevalence of 10.6%.4 Moreover, giardiasis has been shown to be markedly associated
with hypozincaemia in the Iranian population.5 In Mahyar et al.’s study, stool cultures were used to determine
the causative pathogens in their studied population.1 No growth was seen in 32 (53.3%) patients while 28 (46.7%)
patients were found to have bacterial diarrhoea caused by pathogenic Escherichia coli (n = 15), Shigella (n = 10) and
Salmonella (n = 3).1 General stool examinations were not carried out prior to the cultures; this could have resulted
in the exclusion of a significant number of patients with giardiasis-associated acute diarrhoea.1 Accordingly, this
might affect the accuracy of Mahyar et al.’s results.

Secondly, Mahyar et al. studied the correlation between serum zinc levels and various inflammatory
and non-inflammatory variables.1 The study showed a non-significant correlation between these variables
and serum zinc levels; thus, these variables could not be considered predictors of zinc deficiency in
Iranian children with acute diarrhoea.1 This is an interesting observation as it contrasts with previously
reported observations; Strand et al. studied the association between plasma zinc concentration and
several clinical and biochemical variables in a cohort of Nepalese children with acute diarrhoea.6 The
study revealed an association between axillary temperature and plasma zinc concentrations. As such, a
reduction was seen in the mean plasma zinc concentration per degree of increased axillary temperature
(0.59 µmol/L per ºC). Reduced plasma zinc levels were also associated with elevated levels of C-reactive protein,
dysentery and decreased plasma albumin levels. The study also found that there were increased levels of plasma
zinc in children who were dehydrated compared to those who were not.6

Mahmood D. Al-Mendalawi
Department of Paediatrics, Al-Kindy College of Medicine, Baghdad University, Baghdad, Iraq
E-mail: mdalmendalawi@yahoo.com

References
1. Mahyar A, Ayazi P, Chegini V, Sahmani M, Oveisi S, Esmaeily S. Serum zinc concentrations in children with acute bloody and watery

diarrhoea. Sultan Qaboos Univ Med J 2015; 15:e512–16. doi: 10.18295/squmj.2015.15.04.012.

2. World Health Organization. The treatment of diarrhoea: A manual for physicians and other senior health workers. From: www.who.int/
maternal_child_adolescent/documents/9241593180/en/ Accessed: Dec 2015.

3. El-Mohammady H, Mansour A, Shaheen HI, Henien NH, Motawea MS, Raafat I, et al. Increase in the detection rate of viral and parasitic
enteric pathogens among Egyptian children with acute diarrhea. J Infect Dev Ctries 2012; 6:774–81. doi: 10.3855/jidc.2349.

4. Daryani A, Sharif M, Nasrolahei M, Khalilian A, Mohammadi A, Barzegar G. Epidemiological survey of the prevalence of intestinal
parasites among schoolchildren in Sari, northern Iran. Trans R Soc Trop Med Hyg 2012; 106:455–9. doi: 10.1016/j.trstmh.2012.05.010.

5. Zarebavani M, Dargahi D, Einollahi N, Dashti N, Mohebali M, Rezaeian M. Serum levels of zinc, copper, vitamin B12, folate and
immunoglobulins in individuals with giardiasis. Iran J Public Health 2012; 41:47–53.

6. Strand TA, Adhikari RK, Chandyo RK, Sharma PR, Sommerfelt H. Predictors of plasma zinc concentrations in children with acute diarrhea.
Am J Clin Nutr 2004; 79:451–6.

letter to the editor

Sultan Qaboos University Med J, February 2016, Vol. 16, Iss. 1, pp. e123–124, Epub. 2 Feb 16
Submitted 3 Dec 15
Accepted 20 Dec 15

doi: 10.18295/squmj.2016.16.01.027

http://dx.doi.org/10.18295/squmj.2015.15.04.012
http://dx.doi.org/10.3855/jidc.2349
http://dx.doi.org/10.1016/j.trstmh.2012.05.010

Re: Serum Zinc Concentrations in Children with Acute Bloody and Watery Diarrhoea

e124 | SQU Medical Journal, February 2016, Volume 16, Issue 1

Response from the Authors

Sir,

We thank you for your comments on our recently published article.1 As mentioned in our article, the main
objectives of our study were to compare serum zinc levels in children with acute diarrhoea and in healthy control
subjects, as well as to compare serum zinc concentration in children with acute watery versus bloody diarrhoea,
regardless of the identification of aetiological factors such as rotavirus infection or giardiasis.

The diagnosis of acute diarrhoea, acute watery diarrhoea and dysentery was based on the definitions of the
World Health Organization.2 In general, our goal was to prove that patients with acute diarrhoea, particularly acute
bloody diarrhoea, have low concentrations of serum zinc. We aimed to suggest that zinc should be prescribed to
all patients with acute diarrhoea regardless of their aetiologic factors. In developing countries, certain diagnostic
facilities (including cultures, rapid diagnostic or polymerase chain reaction tests) for the diagnosis of aetiological
agents are unavailable. Giardiasis can present as acute diarrhoea and the diagnosis is traditionally established by
microscopic evidence of trophozoites or cysts in stool specimens. However, stool enzyme immunoassay or direct
fluorescent antibody tests for Giardia antigens are the tests of choice for giardiasis. Under certain conditions, it
may be necessary to use other diagnostic methods such as aspiration or biopsy of the duodenum or upper jejunum.3

*Abolfazl Mahyar,1 Parviz Ayazi,1 Victoria Chegini,1 Mehdi Sahmani,2 Sonia Oveisi,3 Shiva Esmaeily4

Departments of 1Pediatrics and 4Statistics and Centres for 2Cellular & Molecular Research and 3Metabolic Diseases Research, Qazvin
University of Medical Sciences, Qazvin, Iran
*Corresponding Author e-mail: abolfazl473@yahoo.com

References
1. Mahyar A, Ayazi P, Chegini V, Sahmani M, Oveisi S, Esmaeily S. Serum zinc concentrations in children with acute bloody and watery

diarrhoea. Sultan Qaboos Univ Med J 2015; 15:e512–6. doi: 10.18295/squmj.2015.15.04.012.

3. John CC. Giardiasis and balantidiasis. In: Kliegman RM, Stanton B, St. Geme J, Schor NF, Eds. Nelson Textbook of Pediatrics, 20th ed.
Philadelphia, Pennsylvania, USA: Elsevier, 2015. Pp. 1692–94.

http://dx.doi/org/10.18295/squmj.2015.15.04.012