title: Frequency of Blood-tissue Parasitic Infections in Patients with Multiple Sclerosis, as Compared to their Family Members.
abstract: BACKGROUND
  Multiple Sclerosis (MS) is a chronic demyelinating disease of the central nervous system which has been identifies more prevalent in economically developed countries than in the developing countries. Low prevalence of parasitic infections (which can activate immune response and prevent or modulate damage to host antigens) in these areas is among the possible responsible factors for such a difference. In this study we aimed to compare frequency of blood-tissue parasitic infections in patients with MS, as compared to their healthy family members.
  
  
  METHODS
  This study was conducted on 50 relapsing remitting MS patients and 50 family members attending MS clinic at Alzahra Hospital. IgM and IgG anti-Toxoplasma gondii were measured. Given the high prevalence of cutaneous leishmaniasis in Isfahan, all the participants were also examined for protozoan leishmania microscopically. Furthermore malaria parasite was investigated.
  
  
  RESULTS
  Eighteen patients and 24 healthy family members had positive test in IgG Toxoplasma gondii(P = 0.09). In both groups, there was no positive IgM Toxoplasma gondii. In investigating leishmania, only 3 participants in the case group and 2 in the control tested positive (P = 0.25). No case of malaria was found among the participants.
  
  
  CONCLUSIONS
  Our results showed a mismatch with hygiene hypotheses examined. However, considering that the prevalence of parasites varies with time, and depends on numerous epidemiological factors; these results do not discredit the theory investigated.
authors.affiliation: Department of Mycology and Parasitology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Nader
authors.initials: N
authors.lastname: Pestehchian
authors.affiliation: Department of Neurology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Etemadifarr
authors.affiliation: Department of Mycology and Parasitology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hossein-Ali
authors.initials: HA
authors.lastname: Yousefi
authors.affiliation: Medical Students' Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Chiani
authors.affiliation: Medical Students' Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Neda
authors.initials: N
authors.lastname: Aslani
authors.affiliation: Medical Students' Research Center, Isfahan University of Medical Sciences, Isfahan, Iran ; Department of medicine, Isfahan Research Committee of Multiple Sclerosis, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Nasr
keywords: Blood-tissue parasitic; cutaneous leishmaniasis; malaria; multiple sclerosis; toxoplasmosis