Increased values of mean platelet volume and platelet size deviation width may provide a safe positive diagnosis of idiopathic thrombocytopenic purpura.
BACKGROUND
It has been shown recently that platelet indices like mean platelet volume (MPV), platelet size deviation width (PDW) and platelet-to-large-cell ratio (P-LCR) are helpful in the discrimination between hyperdestructive thrombocytopenia like idiopathic thrombocytopenic purpura (ITP) and hypoproductive thrombocytopenia (HT). The aim of the study is to assess the reliability of these indices in the differentiation of ITP from other thrombocytopenias.


METHODS
We recruited 134 thrombocytopenic patients (69 men, 65 women) who were divided into two groups according to the underlying disease: group I (n = 63) included ITP patients, whereas group II (n = 71) included patients with HT due to myelosuppression secondary to chemotherapy for hematological malignancies. Platelet indices were derived from a Sysmex automated cell counter. Sensitivity, specificity, positive prognostic value, negative prognostic value, efficiency and Youden index were calculated.


RESULTS
Concerning MPV and PDW indices, sensitivity, specificity, positive prognostic value, negative prognostic value, efficiency and Youden index were 100% for the diagnosis of ITP. On the contrary, the values for P-LCR were significantly lower.


CONCLUSIONS
MPV and PDW can be safely relied on for a positive diagnosis of ITP. MPV and PDW were superior to P-LCR.
First Propedeutic Department of Internal Medicine, AHEPA Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece. ntaiosgeorge@yahoo.gr
George
G
Ntaios
Athanasios
A
Papadopoulos
Anastasia
A
Chatzinikolaou
Zoi
Z
Saouli
Paraskevi
P
Karalazou
Georgia
G
Kaiafa
Fotios
F
Girtovitis
Zisis
Z
Kontoninas
Christos
C
Savopoulos
Apostolos
A
Hatzitolios
Stiliani
S
Alexiou-Daniel
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use; D001792:Blood Platelets / Q000648:ultrastructure*; D048429:Cell Size; D003937:Diagnosis, Differential; D005260:Female; D019337:Hematologic Neoplasms / Q000150:complications / Q000188:drug therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000097:blood / Q000175:diagnosis; D010976:Platelet Count / Q000295:instrumentation; D011379:Prognosis; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D013921:Thrombocytopenia / Q000097:blood / Q000139:chemically induced