Dr. Apoorva Jayarangaiah MARSHFIELD CLINIC- Saint Joseph s Hospital

Transcription

1 Dr. Apoorva Jayarangaiah MARSHFIELD CLINIC- Saint Joseph s Hospital A 30 year old G1P0 female of Korean descent was referred by her OBGYN during her 2 nd trimester to the Hematology Clinic for evaluation of persistent thrombocytopenia of 11,000. ü ü Thrombocytopenia dates back prior to pregnancy Typically, patient s platelet counts ranged from 20,000 to 30,000 1

2 } At the age of 16 Menorrhagia & Petechiae Platelet count: 10,000 Other causes excluded; HIV, EBV, autoimmune drugs, FH Peripheral smear: Giant platelets Immune thrombocytopenic purpura Bone marrow Bx: increased number of megakaryocytes with normal morphology Coagulation panel: increased BT, normal PT, PTT Immune Thrombocytopenic Purpura } She was initiated on steroids and IV immunoglobulins. } She then underwent splenectomy, as there was no response to initial treatment. } Patient was also maintained on Rituximab for a short period with no improvement. 2

3 } Menorrhagia had been controlled with oral contraceptive pills } She had received weekly injections of Romiplastin to help decrease her bleeding risk. } She was supported by repeated platelet transfusions perioperatively and during symptomatic phases. 4 years after the diagnosis of ITP, the patient presented with renal failure, hematuria and proteinuria. She quickly progressed to End Stage Renal Disease (ESRD). o Around the same time, she also developed cataracts and progressive sensorineural hearing loss. 3

4 Nephritis Alport Syndrome Cataracts hearing loss Due to presence of syndromic features of sensorineural hearing loss, renal failure and cataracts diagnosis was presumed to be Alport s syndrome Alport syndrome o Patient underwent renal transplant- living related kidney donor (from half brother). o Currently maintained on Tacrolimus and Prednisone 5 mg. 4

5 } The patient is asymptomatic. } Vital signs are within normal limits. Physical examination is normal; No petechiae or ecchymoses noted. LABAROTORY WBC: 10.3 Hemoglobin: 14.0 Hematocrit: 43 Platelet count:11,000 5

6 Macrothrombocytopenia Refractory ITP Nephritis Alport Syndrome Cataracts hearing loss Nephritis Alport s Syndrome??? Cataracts hearing loss Macrothrombocytopenia 6

7 Genetic testing ü First discovered by Epstein in 1972 ü 4 overlapping syndromes of MYH-9 disorders: Epstein Syndrome, May-Hegglin, Sebastian, Fechtner Syndrome 7

8 Non muscle myosin heavy chain gene (NMMHC-IIA) ü Present in platelets as well kidneys, leukocytes, lens and cochlea ü Important cytoskeletal contractile protein in hematopoietic stem cells - Thrombocytopenia Immune Thrombocytopenic Purpura Epstein syndrome (MYH-9 related disorders) Alport s syndrome Genetics Acquired vs congenital AD; Congenital XD; Congenital Pathogenesis Platelet-glycoprotein specific auto abs Peripheral smear Bone marrow biopsy Giant platelets (~ 10%) Increased megakaryocytes w/ normal morphology MYH-9 gene- NMMHC-IIA mutation Giant platelets; MPV Neutrophilic inclusions bodycytoplasmic aggregates of NMMHC-IIA Increased megakaryocytes w/ normal morphology Low Platelets ü ü Type IV collagen Normal - - Other clinical findings None deafness, Cataracts, Nephritis deafness, Nephritis, Cataracts, Lenticonus 8

9 } Importance of differentiating between MYH-9 gene disorders and ITP } Early recognition of MYH-9 disorders can be beneficial in avoiding unnecessary procedures, referral to genetic counseling and preventative measures } Law of diagnostic parsimony or Occam s Razor } Althaus K, Greinacher A. MYH-9 Related Platelet Disorders: Strategies for Management and Diagnosis. Transfus Med Hemother, 2010 (5); } Vassallo D, Erekosima I et al. Myosin heavy chain-9- related disorders (MYH9-RD); a case report. Clin Kidney J 2013 Oct(5); } Ryhanen SJ, Antitila P. Hereditary macrothrombocytopenia and hearing loss. Duodecim 2015; 131(9); } Kaushansky, K., & Williams, W. J. (2010). Williams hematology. New York: McGraw-Hill Medical. 9