We refer you to a well-researched Website on E-Medicine Journal by the World Medical Library : Hydrops Fetalis.
We have looked in many directions because many heterogeneous disorders result in hydrops fetalis on the one hand and on the other hand, our case is quite complex with significant dysmorphism on top of hydrops.
You will find hereafter some interesting Websites :
Genetic diseases in general
Neonatal Diseases and Abnormalities (including Pediatrics) - Karolinska Institutet (Sweden)
Genetic Disorders and Birth Defects - Genetic Information And Patient Services (USA)
National Center for Biotechnology Information - See PubMedline and OMIM
The Dysmorphic Human-Mouse Homology Database - Database on dysmorphism
Office of Rare Diseases - ORD (USA)
National Organization for Rare Disorders - NORD (USA)
Contact a Family (UK)
Orphanet (France) - Database of rare diseases and orphan drugs
Federation of Orphan Genetic Diseases (France)
Lysosomal or metabolic disorders
Association "Vaincre les maladies lysosomales" (France)
Rare Genetic Diseases In Children - New York University School of Medicine
Nutritional and Metabolic Diseases - Karolinska Institutet (Sweden)
Biochemical Genetics Laboratory - University of California San Diego
See particularly List of Biochemical Genetics Labs and Tests by Diseases
Rhabdomyoma and cardiopathy
Cardiac + Myopathy - Washington University School of Medicine
Cardiac rhabdomyoma - Medical site "thefetus.net"
Myocardiopathies mitochondriales de l'enfant - Review "Médecine thérapeutique/Pédiatrie"
L'imagerie dans les cardiopathies congénitales - French Council of the Teachers of Radiology
Seckel Syndrome and birth defects
Bases semeiologiques des dysmorphies foetales-French Council of the Teachers of Radiology
Syndrome de Seckel - Centres Butters-Savoy et Horizon (Quebec)
Bird-Headed Dwarfism - Birth Disorder Information Directory
Multiple congenital anomaly Syndromes Database - US National Library of Medicine
Hygeia Foundation for Perinatal Loss & Bereavement (USA)