sickle cell disease, hemechip

Conditions: Sickle Cell Disease

Summary: sickle cell disease is very common in nigeria. early diagnosis is important to prevent or reduce serious complications from the disease and to enable children stay healthy. to this end, the investigators would like to test a new, simple and quick device called the hemechip to determine if it can detect whether or not someone has sickle cell disease. the investigators will compare the results obtained with the hemechip with a standard method of diagnosing sickle cell disease known as isoelectric focusing (ief) or high performance liquid chromatography (hplc).if the investigators show that the new device can differentiate between children who have sickle cell disease and those who don't as successfully as the ief or hplc, they estimate a sharp increase in the use of this device in many countries especially in africa due to its lower cost

sickle cell disease (scd) is a group of inherited disorders of haemoglobin (hb) synthesis, first described in the medical literature by james herrick in 1910. each year about 300,000 infants are born with scd, including more than 200,000 cases in subsaharan africa alone. in nigeria alone, there are over 150,000 of these children born annually and it is estimated that between 50-90% of these children die before their fifth birthday. overall, in the region, 6% of all childhood mortality in children less than 5 years of age is due to scd complications and infections. vaso occlusive crisis and anemia are serious complications of scd, with infection often being the major cause of hospitalizations, crisis and death. scd is caused by a point mutation in the sixth codon of the beta globin chain that produces normal hb (hba). this substitution of hydrophilic glutamic acid with hydrophobic valine produces sickle hb (hbs), which is abnormally polymerized at low oxygen conditions causing sickling. abnormal polymerization of hbs affects red cell membrane properties, shape, and density, and subsequent critical changes in inflammatory cell and endothelial cell function. the clinical consequences of scd include painful crises, widespread organ damage, and early mortality. current standard practices for diagnosing scd are high performance liquid chromatography (hplc) and bench-top hb electrophoresis. these two approaches, however, require trained personnel and state-of-the-art facilities, both of which may be lacking in many parts of sub-saharan africa where the disease is most prevalent. these laboratory methods also carry significant costs which may be unaffordable for most patients. hemechip diagnostic system offers an original and innovative solution, leveraging a novel engineering approach, to point of care (poc) diagnosis of scd. hemechip separates haemoglobin protein types in a miniscule volume of blood (1μl) on a piece of cellulose acetate paper that is housed in a micro-engineered chip with a controlled environment and electric field. differences in hb mobilities allow separation to occur within the cellulose acetate paper. a micro-engineered design and multiple layer lamination approach are utilized in fabricating the hemechip. the design allows rapid manual assembly and results are available within a few minutes of performing the test. hemechip can also integrate with a mobile user interface (e.g. iphone, ipod), which shows the test result quantitatively and objectively on the screen. hemechip can be used by anyone after a short (30 minute) training, eliminating the need for highly skilled personnel.

Eligibility criteria:
inclusion criteria: * fever or hypothermia (temp ≥38 c or ≤36 c) plus one of the following (prostration, excessive crying, poor feeding, altered consciousness, convulsion, difficulty breathing, profuse vomiting, diarrhea) \& rapid breathing (0-2months\>60 breaths/min, 3-12months \>50 breaths/min, 13- 59 months \> 40 breaths /min) * provision of signed and dated written informed consent by parent or guardian exclusion criteria: * parent of child chooses to opt out of the study after initial consent. * blood transfusion within 3 months of study enrollment. * presence of condition or abnormality that in the opinion of the investigator would compromise the safety of the child or the quality of the data.