A photo of Omar Niss.

Member, Division of Hematology

Assistant Professor, UC Department of Pediatrics



Board Certified

My Biography & Research

Additional Languages

Arabic, French

Clinical Interests

Pediatric hematology; sickle cell disease; hemoglobinopathies; congenital anemias; immune mediated cytopenia

Research Interests

Cardiopulmonary complications of sickle cell disease; congenital anemias

Academic Affiliation

Assistant Professor, UC Department of Pediatrics

Clinical Divisions

Cancer and Blood Diseases, Sickle Cell and Hemoglobin Disorders, Cardio-Oncology

Research Divisions


Blog Posts

My Locations

My Education

MD: Jordan University of Science and Technology, 2004.

Residency: Pediatrics, University of Nebraska Medical Center, Omaha, NE, 2010.

Fellowship: Pediatric Hematology Oncology, Cincinnati Children’s Hospital Medical Center, 2013; Sickle Cell Scholar, Cincinnati Children’s Hospital Medical Center, 2014.

Certification: Pediatrics, 2010; Pediatric Hematology/Oncology, 2015.

My Publications

Implementation of near-universal hydroxyurea uptake among children with sickle cell anemia: A single-center experience. Karkoska, K; Todd, K; Niss, O; Clapp, K; Fenchel, L; Kalfa, TA; Malik, P; Quinn, CT; Ware, RE; McGann, PT. Pediatric Blood and Cancer. 2021; 68.

Hydroyxurea improves cerebral oxygen saturation in children with sickle cell anemia. Karkoska, K; Quinn, CT; Niss, O; Pfeiffer, A; Dong, M; Vinks, AA; McGann, PT. American Journal of Hematology. 2021; 96:538-544.

Congenital dyserythropoietic anemia type I: First report from the Congenital Dyserythropoietic Anemia Registry of North America (CDAR). Niss, O; Lorsbach, RB; Berger, M; Chonat, S; McLemore, M; Buchbinder, D; McCavit, T; Shaffer, LG; Simpson, J; Schwartz, JH; et al. Blood Cells, Molecules, and Diseases. 2021; 87.

Left atrial dysfunction in sickle cell anemia is associated with diffuse myocardial fibrosis, increased right ventricular pressure and reduced exercise capacity. Alsaied, T; Niss, O; Tretter, JT; Powell, AW; Chin, C; Fleck, RJ; Cnota, JF; Malik, P; Quinn, CT; Nagueh, SM; et al. Scientific Reports. 2020; 10.

Hydroxyurea Optimization through Precision Study (HOPS): study protocol for a randomized, multicenter trial in children with sickle cell anemia. Meier, ER; Creary, SE; Heeney, MM; Dong, M; Appiah-Kubi, AO; Nelson, SC; Niss, O; Piccone, C; Quarmyne, MO; Quinn, CT; et al. Trials. 2020; 21.

Reversible Myelofibrosis in Pediatric Renal Osteodystrophy. Sabulski, A; Hughley, E; Nehus, EJ; Grier, DD; Niss, O. Journal of Pediatrics. 2020.

Lymphopenia in adults after the Fontan operation: prevalence and associations. Alsaied, T; Possner, M; Brown, N; Almeneisi, H; Szugye, C; Trout, AT; Niss, O; Palermo, JJ; Zafar, F; Dillman, JR; et al. Cardiology in the Young. 2020; 30:641-648.

Progression of albuminuria in patients with sickle cell anemia: a multicenter, longitudinal study. Niss, O; Lane, A; Asnani, MR; Yee, ME; Raj, A; Creary, S; Fitzhugh, C; Bodas, P; Saraf, SL; Sarnaik, S; et al. Blood Advances. 2020; 4:1501-1511.

Congenital Dyserythropoietic Anemia Type I Due to Biallelic CDAN1 mutations: Report from the Congenital Dyserythropoietic Anemia Registry (CDAR). Niss, O; Lorsbach, RB; Buchbinder, DK; Chonat, S; McLemore, ML; McCavit, T; Schwartz, JH; Meznarich, J; Seu, K; Zhang, W; et al. Blood. 2019; 134:3521-3521.

Robust clinical and laboratory response to hydroxyurea using pharmacokinetically guided dosing for young children with sickle cell anemia. McGann, PT; Niss, O; Dong, M; Marahatta, A; Howard, TA; Mizuno, T; Lane, A; Kalfa, TA; Malik, P; Quinn, CT; et al. American Journal of Hematology. 2019; 94:871-879.