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Significant weight loss interpretation 
Non intentional weight loss is an alarming sign if the weight loss was of more than 20% of the actual weight in a matter of less than 6 months without any diet or exercise change, its an indicator of an underlying active metabolic state that should be detected and treated accordingly after consultation of Internest 
Investigations 
After proper physical exam you should do cbc to detect anemia, high WBC ( indicator of blood malignancy), Blood sugar testing to detect diabetes, Liver enzymes ( AST,ALT,ALP,Total Protein ,Albumin) in addtion to urine analysis to look for proteinurea that may cause lower limb edema, Kidney function testing ( Urea ,Cr ). Stool blood occult test to detect blood in the stool and if positive you should do colonoscopy, Thryoid fuction testing (TSH,T4)
Causes 

• Blood diseases 
• Liver cirhosis 
• chronic kidney diseases 
• Diabetes 
• Malabsorbtion 
• Thyroid dysfunction 
• Colonic tumors 

Our advice 
You are adviced to have a healthy diet, avoid smoking and have regular exercise