hala ahmed gaber elnahas

@mans.edu.eg

medical Parasitology Department , Faculty of Medicine
haelnahas@mans.edu.eg

RESEARCH, TEACHING, or OTHER INTERESTS

Medicine, Parasitology
20

Scopus Publications

Scopus Publications

  • Association Between Giardia Genotype and Oxidative Stress Biomarkers Among Giardia-Infected Children: A Case–Control Study
    Amira Ismail, Aida A. Abdel-Magied, Abeer A. Elhenawy, Hala A. El-Nahas
    Acta Parasitologica, 2022
    Purpose Giardia duodenalis is the most common worldwide intestinal protozoal infection. The implication of free radicals in organ injury occurs through oxidative stress. Infections as Giardia may act as a triggering or promoting factor for oxidative stress, particularly in children with compromised immunity. Besides, the effect of Giardia genotype on oxidative stress status is yet to be explored. Therefore, we sought to compare the oxidative stress status between Giardia positive cases (case group) and Giardia negative cases (control group), and to explore the association between Giardia genotype and the level of oxidative stress markers in Giardia-infected children, especially those receiving immunosuppressive therapy. Methods Pediatric patients attending Mansoura University Children Hospital in the period from April 2015 to October 2016 were enrolled. Both case (n = 50) and control (n = 50) groups were further subdivided into immunosuppressive therapy recipients (ITR) and non-immunosuppressive therapy recipients (NITR). Genotyping of Giardia from positive stool samples by PCR was carried out, and oxidative stress markers were measured from venous blood samples. Results Giardia positive cases had higher levels of Malondialdehyde (MDA) and lower levels of total antioxidant capacity (TAC). MDA highest level was associated with mixed genotypes A and B, while the highest TAC level was associated with Giardia genotype A in both ITR and NITR cases. Conclusion Elevated oxidative stress biomarkers in pediatric patients infected with specific Giardia genotypes should receive considerable attention, because if prompt treatment is not conducted, oxidative damage may occur in patients with giardiasis, especially those receiving immunosuppressive therapy.
  • Cryptosporidiosis in patients with diarrhea and chronic liver diseases
    Nasser Mousa, Ahmed Abdel-Razik, Hala El-Nahas, Atef El-Shazly, Mohammad Abdelaziz, et al.
    Journal of Infection in Developing Countries, 2014
    Introduction: The aim of this study was to evaluate the epidemiology and clinical significance of Cryptosporidium in patients with diarrhea and chronic liver diseases. Methodology: The study included 150 patients with chronic liver diseases and diarrhea, and 50 subjects with diarrhea as a control group. Stool samples were screened for the presence of Cryptosporidium by microscopic examination after modified Ziehl-Neelsen staining and detection of Cryptosporidium coproantigen by enzyme-linked immunosorbent assay (ELISA). Results: The prevalence of Cryptosporidium infection in patients with chronic liver diseases was 30% (45/150) versus 14% (7/50) in controls. Cryptosporidium infection increased with the progression of chronic liver diseases from Child-Pugh class A to Child-Pugh class C (p< 0.001) and from model for end-stage liver disease (MELD) score ≤ 9 to MELD score > 9 (p< 0.031). Nine patients in Child-Pugh class C with diarrhea associated with Cryptosporidium infection developed hepatic encephalopathy, and only diarrhea was identified as a precipitating factor for hepatic encephalopathy. Conclusions: Cryptosporidium is one of the important causes of diarrhea in patients with chronic liver diseases. The infection significantly increased with the progression of chronic liver diseases. In patients with advanced chronic liver diseases, Cryptosporidium infection may be a precipitating factor of hepatic encephalopathy.
  • Toxoplasma gondii infection among chronic hepatitis C patients: A case-control study
    Hala A El-Nahas, Nora L El-Tantawy, Raghda E Farag, Argaya MA Alsalem
    Asian Pacific Journal of Tropical Medicine, 2014
  • Giardia diagnostic methods in human fecal samples: a comparative study.
    Hala A. El-Nahas, Dalia A. Salem, Abeer A. El-Henawy, Hosam I. El-Nimr, Hasan A. Abdel-Ghaffar, et al.
    Cytometry Part B Clinical Cytometry, 2013
    Several methods were tried for Giardia detection in stool. This study aimed to compare between the results of ordinary microscopy, direct immunofluorescence assay (DIF), and flow cytometry (FC) for the detection of Giardia cyst in human stool samples. The study included 84 children recruited from outpatient clinics of Mansoura University Children Hospital. Fecal samples were processed and examined for Giardia cysts using conventional microscopy, DIF, and FC. Among 84 fecal samples, 40 (47.6%) were diagnosed as Giardia‐positive by saline wet mount, while DIF and FC detected 52 (61.9%), and 38 (45%) Giardia‐positive cases, respectively. When compared with DIF as a gold standard method, ordinary microscopy had 76.9% sensitivity and 100% specificity while the FC had a sensitivity of 73.1% and 100% specificity, with statistically significant differences between DIF and the other two methods (P < 0.05). DIF was able to detect as few as 500 cysts/g of concentrated stool, yielding a threshold higher than ordinary microscopy (1,800 cyst/g) even after concentration. It is concluded that direct microscopic examination is reliable in Giardia diagnosis as a first choice test. DIF is an excellent technique in clinically suspected cases after negative microscopy. FC was found to be less sensitive to obtain accurate organisms' count but it could be an effective alternative method for the detection of Giardia cysts, especially for large‐scale epidemiological studies or extensive surveillance programs as it has the beneficial attribute of speed and do not depend on an experienced microscope viewer. However, DIF remains the gold standard while FC still requires significant technical improvements before it can compete with DIF for Giardia diagnosis. © 2012 International Clinical Cytometry Society
  • Diagnosis of Giardia and Cryptosporidium infection in children with diarrheal illness using rapid immunochromatographic assay
    Archives of Clinical Microbiology, 2012
  • Impact of basic lymphedema management and antifilarial treatment on acute dermatolymphangioadenitis episodes and filarial antigenaemia
    HA El-Nahas, AM El-Shazly, M Abulhassan, NA Nabih, N Mousa
    Journal of Global Infectious Diseases, 2011
    Background: A major factor in the progression of lymphedema is acute dermatolymphangioadenitis (ADLA). Aims To study ADLA episodes and antigenaemia in patients with different grades of filarial lymphedema at pre- and two years post-treatment. Setting and Design: A prospectively conducted study from May 2008 through May 2010. Patients and Methods: Forty five patients complaining of limb swelling with present or past history of limb redness suggestive of ADLA attacks were included. Patients were clinically examined for lymphedema grading, detection of potential entry points and diagnosis of microfilaraemia. Wuchereria bancrofti antigen titer was estimated by “Trop-Ag W. Bancrofti” ELISA kit. Basic lymphedema management and treatment with antifilarial drugs were applied. Statistical Analysis Mann–Whitney test and Chi-square test were used. Results: The number of ADLA attacks in the pretreatment period, ranged from one to three per year. Mean duration of the attacks was 3.87±0.79 days. Entry points were detected in 82% of cases. The study revealed statistical significance between extension and grade of lymphedema and number of ADLA attacks per year (P=0.018 and 0.022, respectively). Microfilaraemia was detected in four cases and positive filarial antigenaemia were detected in 29 patients (64.4). The number of ADLA attacks per year significantly decreased from the pre-treatment period (mean: 2.05±0.560) to be 1.23±0.706 after one year and 0.89±0.575 after two years post treatment. There was a significant decrease in the mean antigen titer one year and two years after treatment. Conclusion: Basic lymphedema management is effective for controlling ADLA attacks in areas where lymphatic filariasis is endemic.
  • Comparative study between immunohistochemical grading and giardia genotyping among symptomatic and asymptomatic humans.
    Egyptian Journal of Immunology Egyptian Association of Immunologists, 2007
  • Diagnostic criteria for house dust mites sensitized allergic patients.
    Journal of the Egyptian Society of Parasitology, 2007
  • Pulmonary parasitosis: Applied clinical and therapeutic issues
    Sameh Ibrahim Sersar, Hala Ahmed Elnahas, Abdel Basset Mohammed Saleh, Sherif Abdou Moussa, Wael A. Abdel Ghafar
    Heart Lung and Circulation, 2006
  • The reflection of control programs of parasitic diseases upon gastrointestinal helminthiasis in Dakahlia Governorate, Egypt.
    Journal of the Egyptian Society of Parasitology, 2006
  • A diagnostic dilemma of right lower lobe collapse caused by pulmonary bilharsiasis
    S. Sersar, Reda Ahmed Abulmaaty, Hala Ahmed Elnahas, S. Moussa, U. Shiha, et al.
    Heart Lung and Circulation, 2006
  • Present situation of house dust mites in Dakahlia Governorate, Egypt.
    Journal of the Egyptian Society of Parasitology, 2006
  • Laparoscopic excision of prostatic hydatid cyst: Case report and review of literature
    Hamdy A. El-Kappany, Ahmed R. El-Nahas, Hala A. El-Nahas
    Journal of Endourology, 2005
  • Serological diagnosis of Trichinella spiralis in experimentally infected mice.
    Journal of the Egyptian Society of Parasitology, 2005
  • Blastocystis hominis among symptomatic and asymptomatic individuals in Talkha Center, Dakahlia Governorate, Egypt.
    Journal of the Egyptian Society of Parasitology, 2005
  • On the main reservoir host of Fasciola in Dakahlia Governorate, Egypt.
    Journal of the Egyptian Society of Parasitology, 2005
  • Cholestasis in human fascioliasis in Dakahlia Governorate, Egypt.
    Journal of the Egyptian Society of Parasitology, 2005
  • Human fascioliasis and anaemia in Dakahlia Governorate, Egypt.
    Journal of the Egyptian Society of Parasitology, 2005
  • Geoparasites in rural Dakahlia Governorate, a preliminary based study for development of the community-based intervention programs.
    Journal of the Egyptian Society of Parasitology, 2005
  • Some molecular aspects in schistosomiasis mansoni and toxoplasmosis.
    Journal of the Egyptian Society of Parasitology, 2005