Brief Answer: History, Examination and workup all needed. Detailed Answer: Hello Mis XXXX! Thank you for asking. i read your concern about the query of a cognitive disorder called NOS( not other wise specified) also known as PDD (pervasive development disorder). Now your query whether possible to diagnose it without blood work or ruling it out , I want you to know that workup is almost inevitable as that confirms the diagnosis. But yes physical examination and history has specific points which makes a doctor very suspicious of the disease. Hand-wringing, hyperventilation, or both; deranged head circumfrences either large > 90 percentile or small less than 90 percentile; people with PDD often have constipation, diarrhea, or reflux; that they may lack the verbal ability to report; eczema; wheezing, and poor weight gain and food allergies are also very common. Then doctors assessment of language development; social integration assessment; social interactions; stereotypic behaviours and last but not the least social communication questionnaire (SCQ) which pretty much arouses suspicion of whats going on. But..... To be sure of the etiology and cause and most importantly to avoid LAWSUIT put by wrongly diagnosed patient , doctors stay on the safe road and they advise work up which comprises of High-resolution cytogenic studies with fluorescence in situ hybridization (FISH) testing for Prader-Willi, Angelman, and XXXXXXX syndromes Creatine phosphokinase measurement - To rule out muscular dystrophy Determination of lead level - To rule out lead poisoning Urine organic acid test Plasma amino acid test Lactate and/or pyruvate test - To rule out mitochondrial disorders Serum ammonia test - To rule out urea cycle defects Test for very long fatty acids - To rule out peroxisomal disorders Test of thyroid-stimulating hormone - To rule out hypothyroidism Gene sequencing for MECP2 Hearing testing Comparative genomic hybridization (CGH) Imaging studies like Ct, MR, SPECT PET scans etc Electroencephalography Psychological and Neuropsychological Testing . Now your last question of need to repeat depends upon the error. If the labs are done perfectly so then I guess no need to repeat them unless doctor has something in mind which will be in patients favour. SO in Nutshell, i want you to trust your doctor and let him decide what to do and what not to as he knows your best interest. If you have any more queries please feel free to ask other wise kindly close the discussion and rate the answer as per your experience. Good Luck and may the odds be ever in your favour. Regards Dr. S Khan

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