CASE IS OPEN FOR DISCUSSION:  
 
33 yrs old male with some teeth irregularities.  
CLIN HISTORY: non healing anal fissure, oral infections (post extraction of teeth), mediastinitis.  
EPISODE 1: In 2018 bone marrow biopsy taken: MDS-EB1. CD34+ blasts elevated 7-8% and visible in IH.  
Molecular: Karyotype normal. No defining AML mutations found.  
Clin: Fever, oral ulcerations, in flow/aspirate: MDS changes + ~8% blasts: CD45+ dim; CD34+; CD38+ het; CD117+ het; HLADR+ CD13+ CD33+ CD11c+ het; cMPO+ het; CD5+ dim; CD7+ dim; CD4/CD11b/CD14/CD36/CD56/CD64/sCD3/cCD79a(-).  
TREATMENT: transfusions only.  
 
EPISODE 2: After treatment another threpine was taken with DIAMETRALLY other picture: expansile NASDE+ immature atypical granulopoiesis with depressed or extinct erythros and megas (as in AML cases).  
But IH anonymous:  
MPO+ immature granulopoiesis with majority WT1 (++), CD99(+/++); p53 (+++); CMYC(++/+++) 70%; ERG1 (+++) 100%; CD2(-); CD30(-); CD14(-); CD15(-); CD2/CD5(-); CD56(-); CD4(-); CD11c(-).  
 
FLOW: to be contd (NO DEFINITE BLASTS in the window, but immunophenotype atypical); ~32% young, myeloid cells with abberrant phenotype: CD45+dim, CD34-/+dim (nonspec), CD13+, CD33-/+dim, CD11a+het, CD15+het, CD38+het, HLA-DR-/+ partial, CD56+dim, CD99+dim, CD123+dim, CD133-/+dim, cMPO+ strong, CD7-/+ dim (nonspec?), CD117-, CD11b-, CD14-, CD36-, CD64-, CD96-, CD2-, NG2-, TdT-.  
Not expressing blastic promyelocytic Ags (CD117), abberrantly express CD56, CD99, abberrantly diminished maturation Ags CD33, CD64.  
Additionally ~5,8% CD34+/CD117+ abberrant myeloblasts.  
 
PB:  
WBC (*10^9/l) 1,17 (4,0-9,8)  
NEU (*10^9/l) 0,10 (1,5-6,0)  
RBC (*10^12/l) 3,00 (Male 4,3-5,8)  
HgB (g/l) 90 (Male 128-160)  
Plt (x10^9/l) 52 (140-450)  
 
VULSK aspirate:  
Blasts (threpine) 7,5  
Blastai (marrow.) 5,0  
Siderocytes and sideroblasts 30%, ringed ones 8.  
 
MOLECS: Complex karyotype (7 abberations): 3q, 5q, 6p, 7q deletions, 8 trisomy, 19 monosomy and 15q duplication.  
Bad prognostic group.  
Telomere length NORMAL. Chromosome breakage: NO.  
NGS TSM: TP53 c.857A>C (p.Glu286Ala) mutation.  
 
2 pathogenic mutations of SBDS gene found (Schwachman Diamond anemia): to be more specified soon.  
 
DIAGNOSTIC QUESTIONS:  
1. How interpret EPISODE 2 (AML? Immaturity? No MDS features; depressed mega/erythro) especially comparing with "classic" MDS EB1 in EPISODE 1.  
2. Do immunophenotype CD99+ WT1+ ERG1+p53+CMYC+ only is specific/enough for " NASDE+ BLASTS"/AML or possible in "immature" inherited SD hematopoiesis?  
ThankYou.