HemoChat is an evidence-based AI medical search tool covering all major clinical domains, powered by 46,298 SNOMED-CT concepts, clinical guidelines, and live PubMed literature.

What medical domains does HemoChat cover?

HemoChat covers all major medical domains including cardiology, oncology, neurology, hematology, pulmonology, endocrinology, gastroenterology, psychiatry, nephrology, rheumatology, musculoskeletal, and more — with 46,298 SNOMED-CT concepts.

Is HemoChat a replacement for clinical judgment?

No. HemoChat is for clinical reference only and is not a substitute for professional medical judgment. Always consult qualified healthcare professionals for medical decisions.

What AI technology does HemoChat use?

HemoChat uses a hybrid GraphRAG + VectorRAG pipeline combining Neo4j knowledge graphs with FAISS vector search and an LLM for answer generation.

Lissencephaly syndrome Norman Roberts type — Clinical Guidelines

Overview

Roberts syndrome, also known as Lissencephaly syndrome Norman Roberts type (MIM 268300), is a rare autosomal recessive genetic disorder characterized by severe growth retardation, limb malformations including tetraphocomelia and oligodactyly, facial anomalies, and often internal organ defects 1 10.

Diagnosis

Clinical Features: Pre- and postnatal growth retardation, severe limb shortening with radial defects, oligodactyly, facial clefts, cleft lip/palate, micrognathia, and characteristic facial features 1 3 10.

Cytogenetic Abnormalities: Premature centromere separation and abnormal sister chromatid disjunction in amniocytes or lymphocytes 5 10.

Prenatal Diagnosis: Ultrasound detection of limb deficiencies; serial scans may be necessary 8 5.

Postmortem Findings: Often reveal additional internal anomalies such as dysplastic kidneys, hydronephrosis, and other organ malformations 13.

Management

Supportive Care: Focus on managing complications including respiratory support, feeding difficulties, and orthopedic interventions for joint contractures 1 13.

Genetic Counseling: Essential for families due to autosomal recessive inheritance pattern 1 14.

No Specific Pharmacological Treatment: No evidence supports specific drug treatments; management is primarily symptomatic and supportive 12.

Special Populations

Pregnancy: Prenatal diagnosis possible but requires careful monitoring with serial ultrasounds 8 5.

Pediatrics: Early intervention for developmental delays and physical anomalies is crucial 1 10.

Comorbidities: Thrombocytopenia and renal anomalies may require specific medical management 13.

Key Recommendations

Prenatal Screening for Suspected Cases: Utilize serial ultrasounds to detect limb deficiencies and other anomalies indicative of Roberts syndrome (Evidence: Moderate) 8 5.

Genetic Testing Postnatally: Confirm diagnosis through cytogenetic analysis for premature centromere separation (Evidence: Moderate) 5 10.

Comprehensive Supportive Care Plan: Address multiple organ systems affected, including orthopedic and respiratory support (Evidence: Expert opinion) 1 13.

Genetic Counseling for Families: Essential for understanding inheritance patterns and recurrence risks (Evidence: Expert opinion) 1 14.

References

1 Temtamy SA, Ismail S, Helmy NA. Roberts syndrome: study of 4 new Rgyptian cases with comparison of clinical and cytogenetic findings. Genetic counseling (Geneva, Switzerland) 2006. link 2 Bates AW. Autopsy on a case of Roberts syndrome reported in 1672: the earliest description?. American journal of medical genetics. Part A 2003. link 3 de Ravel TJ, Seftel MD, Wright CA. Tetra-amelia and splenogonadal fusion in Roberts syndrome. American journal of medical genetics 1997. link1096-8628(19970120)68:2<185::aid-ajmg13>3.0.co;2-q) 4 Urban M, Rogalla P, Tinschert S, Krietsch P. Tetraphocomelia and bilateral cleft lip in a historical case of Roberts syndrome [Virchow, 1898]. American journal of medical genetics 1997. link1096-8628(19971031)72:3<307::aid-ajmg11>3.0.co;2-x) 5 Benzacken B, Savary JB, Manouvrier S, Bucourt M, Gonzales J. Prenatal diagnosis of Roberts syndrome: two new cases. Prenatal diagnosis 1996. link1097-0223(199602)16:2<125::AID-PD822>3.0.CO;2-S) 6 Allingham-Hawkins DJ, Tomkins DJ. Heterogeneity in Roberts syndrome. American journal of medical genetics 1995. link 7 Gershoni-Baruch R, Drugan A, Bronshtein M, Zimmer EZ. Roberts syndrome or "X-linked amelia"?. American journal of medical genetics 1990. link 8 Robins DB, Ladda RL, Thieme GA, Boal DK, Emanuel BS, Zackai EH. Prenatal detection of Roberts-SC phocomelia syndrome: report of 2 sibs with characteristic manifestations. American journal of medical genetics 1989. link 9 Fryns JP, Kleczkowska A, Moerman P, van den Berghe K, van den Berghe H. The Roberts tetraphocomelia syndrome: identical limb defects in two siblings. Annales de genetique 1987. link 10 Mann NP, Fitzsimmons J, Fitzsimmons E, Cooke P. Roberts syndrome: clinical and cytogenetic aspects. Journal of medical genetics 1982. link 11 Fryns H, Goddeeris P, Moerman F, Herman F, van der Berghe H. The tetraphocomelia-cleft palate syndrome in identical twins. Human genetics 1980. link 12 Stoll C, Levy JM, Beshara D. Roberts's syndrome and clonidine. Journal of medical genetics 1979. link 13 Waldenmaier C, Aldenhoff P, Klemm T. The Roberts' syndrome. Human genetics 1978. link 14 Freeman MV, Williams DW, Schimke RN, Temtamy SA, Vachier E, German J. The Roberts syndrome. Birth defects original article series 1974. link

Lissencephaly syndrome Norman Roberts type