SERODIAGNOSIS OF CRYPTOSPORIDIOSIS

SUMMARY AND CONCLUSIONThe present study aims to evaluate and compare between MZN and the IFAT for detection of IgG and IgM as well as their relation to age, sex, residence, systemic troubles and degree of diarrhoea.A) Cryptosporidium oocysts antigen was prepared from human stool.B) From all individuals of the present study, the following amples were obtained and investigated as follows:a) Stool samples were examined for detection of:1- Any parasites by direct wet smears and formol- ether sedimentation technique.2- Cryptosporidium oocysts using modified Ziehl- Neelsen stain.b) Blood samples for separation of serum to determine IgG and IgM by IFAT using C. parvum oocysts antigen* The obtained data were tabulated and statistically analysed then summarized in the following points.(1) All Cryptosporidium infected cases were detected in stool samples collected during summer months depending on diarrhoea as the most common symptom.(2) The most rapid, easy and cheap method for detection of Cryptosporidium oocysts was the concentration of stool specimens by formol- ether followed by MZN stain.(3) The best method for preparation of antigen was by sodium chloride floatation, which get rid off large amounts of faecal debris, relatively short processing time (less than 3 hours) and low expense associated with it.(4) The frequency of IgG was 41% and 17.9 in patients excreting oocysts and patients not excreting oocysts in stools respectively.(5) The percentage of IgG was 45.8% and 39% in patients excreting C. parvum oocysts in stool and patients excreting oocysts of C. parvum and other parasites.(6) The frequency of IgM was 83.8% and 14.3% in patients excreting oocysts and patients not excreting oocysts in stool respectively.(7) The percentage of IgM was 83.94% and 83.3% in patients excreting C. parvum oocysts in stool and patients excreting C. parvum oocysts ant other parasites.(8) There were combined presence of IgG and IgM in cases of acute infection on top of chronic. These cases aged 31 – 45 years, complaint of severe diarrhoea and most of them had cancer as systemic troubles.(9) The sensitivity and specificity of IFAT were 98.2% and 71.4% respectively but for IgG were 41% and 83.7% and for IgM were 82% and 85.7%.(10) The use of IFAT with MZN appears to be useful for diagnosis of cryptosporidiosis in acute infection.(11) The most common age affected was (<15 years) as the frequency of infection was 56.4% and this mean that the younger age is more susceptible to infection.(12) The higher positivity percentage in IgM antibodies was in the younger age group (<15 years), (73.4%). The higher positivity percentage in IgG antibodies was in the older age group (>45 years), (71.4%).(13) The males were more susceptible than females among Cryptosporidium infected cases with percentage of (66.7% and 33.3% respectively).(14) The inhabitants of the rural areas appeared to be more susceptible to infection than those of urban area (51.3% and 48.8% respectively) with highly significant difference.(15) Human to human transmission should be considered as important as animal to human transmission.CONCLUSION:1- Cryptosporidiosis is one of the common causes of diarrhoea in human being.2- Direct stool examination by MZN is the method of choice for diagnosis of this infection as stool specimens are obtained without invasive procedure. Theoretically, faeces sample the entire gut, easy and cheap.3- The use of IFAT with MZN may be useful for accurate diagnosis of cryptosporidiosis.4- The sensitivity of IFAT is 41% for IgG and 82% for IgM while specificity is 83.7% for IgG and 85.7% for IgM.5- The increased positivity of IgG with increasing age indicating the prevalence of it in chronic infection and the increased positivity of IgM with decreasing age indicating the prevalence of it in acute infection.6- The younger age was more susceptible to infection.7- Males were more susceptible than females.8- Cryptosporidiosis ia a zoontic disease.RECOMMENDATION:• Ongoing public health measures should continue to emphasize the importance of personal hygiene as well as to provide and monitor the quality of drinking water.• It is likely that cryposporidiosis is under diagnosed because clinicians fail to consider this diagnosis in patients with diarrhoeal illness and do not request stool analysis for C. Parvum, MZN not normally included in routine stool analysis so it must be put as one of the routine laboratory techniques.• The microscopic detection of C. Parvum oocysts is time- consuming requires trained analysts, and is frequently subjected to significant human errors, so need specific method for detection as PCR, FISH and ANN (antificial neural networks).• Using recombinant Cryposporidium protein as antigen needs more evaluation and studies.