Okay PhoenixDown I found a list of differential diagnosis for patients who are suspected to have a connective tissue manifestations. Here they are:
Williams syndrome (WS)
Aarskog-Scott syndrome (faciiogenital dysphasia)
Fragile X syndrome
Achondroplasia and hypochondroplasia
Osteogenesis imperfecta (OI)
Aneuploidies including Down, Turner, Klinefelter syndromes
Also, there are all the other underlying and co-manifestations diseases that go a long with EDS and similar disorders. Like MS, autoimmune, chronic pain and fatigue, features of fibromyalgia, Chiari, bleeding problems, IBS, GERD, osteopenia, POTTS, orthostatic intolerance, adrenocortical insufficiency, celiac disease, malabsorption and other bowel dysfunctions, von Willebrands disease, thrombocytopenia, hypothyroidism, deficiency in vitamins and minerals like D, B12, etc. As you know the list goes on and on…..I hope this helps.