Letters to the Editor
Monocytopenia and infections in chronic lymphocytic leukemia To the Editor: The key role of monocytic/macrophage cells in the immune response is well known (1-2). These cells act as antigen-presenting cells, are involved in cytotoxic functions and are cytokine producers: therefore their importance in the immune defense is more crucial than that of granulocytes. Nevertheless, in hematological disease all therapeutic protocols define infectious risk in relationship to circulating granulocytes and do not consider monocyte levels (3). In B-chronic lymphocytic leukemia (B-CLL) the infectious disease incidence is high and influences patient survival (4). The immunodepression in B-CLL has been reported to be a result of the expansion of the B-neoplastic clone, the impairment of the residual T-cell subpopulation and hypogammaglobulinemia (4). However, we would like to consider, retrospectively, the relationship between monocytopenia and bacterialfviral infections in B-CLL. We observed 107 patients with B-CLL, with a follow-up of at least 17 months. The monocyte counts were performed by automated cytochemistry (Technicon H6000) at least every 3 months. In Table 1, a signdicantly increased incidence of infectious diseases (patients with > 1 infectious episode per year) is evident in CLL patients with consistently less than 200 peripheral blood (PB) monocytes: among these patients, only 1 had hypogammaglobunemia and none was neutropenic. If we distinguish between documented bacterial and viral infections we find a significantly (p = 0.04) increased incidence of documented viral infections in monocytopenic patients (Table 1); in these patients there is also an increased incidence of documented Table 1. 8-CLL patients Monocytes
References 1. Geppert TD, Lipsky PE. Immunoregolatory activities of macrophages. Trans Proc 1988: 6: 1154-1 155. 2. NEVENPJ. The mononuclear phagocyte system. Bull Inst Pasteur 1986: 84: 23-66. 3. VERHOEFJ, ROZEMBERG-ARSKA M, DEKKERAW. Prevention of bacterial and fungal infections in granulocytopenic patients. Eur J Cancer Clin Oncol 1989: 9: 1345-1350. 4. CHAPELHM, BUNCH C. Mechanism of infection in chronic lymphocytic leukemia. Semin Hemat 1987: 24: 291.
Correspondence: Giulio De Rossi, Francesca Romana Mauro, Pierluigi Ialongo, Serelina Coluzzi, Francesco Pizzo Univ. “La Sapienza”, Human Biopathology Dept, Haematology Section Via Benevento 6 00161 Roma Italy.
Monocytes
>zoo p/l
1200 1111 Patients with > 1 infectious epysode per year Documented viral infections (n./patients) Documented bacterial infections
bacterial infections, but no statistically significantly so. The limits of these observations are evident. Some studies have indicated that automated monocyte counts (Technicon H6000) can show some imprecision in degrees. The presence of large numbers of LUC (large lymphocytes and/or blast cells) or peroxidase-deficient neutrophils can increase the monocyte count. This fact is evident in the output listing; therefore microscopic review is advised. Moreover all our evaluations are retrospective and therefore, even if carefully done, will not be randomized. In any case, we would stress that a prospective study on relationship between monocyte PB levels and infections, especially in B-CLL, could be very interesting and could better define the role of monocytopenia in the immune depression of the patient with hematologic disease.
13/18
P=O.Ol
36/89
4/18
P=0.04
5/89
11/ 18
P= NS
33/89
119
Monocytopenia and infections in chronic lymphocytic leukemia To the Editor: The key role of monocytic/macrophage cells in the immune response is well known (1-2). These cells act as antigen-presenting cells, are involved in cytotoxic functions and are cytokine producers: therefore their importance in the immune defense is more crucial than that of granulocytes. Nevertheless, in hematological disease all therapeutic protocols define infectious risk in relationship to circulating granulocytes and do not consider monocyte levels (3). In B-chronic lymphocytic leukemia (B-CLL) the infectious disease incidence is high and influences patient survival (4). The immunodepression in B-CLL has been reported to be a result of the expansion of the B-neoplastic clone, the impairment of the residual T-cell subpopulation and hypogammaglobulinemia (4). However, we would like to consider, retrospectively, the relationship between monocytopenia and bacterialfviral infections in B-CLL. We observed 107 patients with B-CLL, with a follow-up of at least 17 months. The monocyte counts were performed by automated cytochemistry (Technicon H6000) at least every 3 months. In Table 1, a signdicantly increased incidence of infectious diseases (patients with > 1 infectious episode per year) is evident in CLL patients with consistently less than 200 peripheral blood (PB) monocytes: among these patients, only 1 had hypogammaglobunemia and none was neutropenic. If we distinguish between documented bacterial and viral infections we find a significantly (p = 0.04) increased incidence of documented viral infections in monocytopenic patients (Table 1); in these patients there is also an increased incidence of documented Table 1. 8-CLL patients Monocytes
References 1. Geppert TD, Lipsky PE. Immunoregolatory activities of macrophages. Trans Proc 1988: 6: 1154-1 155. 2. NEVENPJ. The mononuclear phagocyte system. Bull Inst Pasteur 1986: 84: 23-66. 3. VERHOEFJ, ROZEMBERG-ARSKA M, DEKKERAW. Prevention of bacterial and fungal infections in granulocytopenic patients. Eur J Cancer Clin Oncol 1989: 9: 1345-1350. 4. CHAPELHM, BUNCH C. Mechanism of infection in chronic lymphocytic leukemia. Semin Hemat 1987: 24: 291.
Correspondence: Giulio De Rossi, Francesca Romana Mauro, Pierluigi Ialongo, Serelina Coluzzi, Francesco Pizzo Univ. “La Sapienza”, Human Biopathology Dept, Haematology Section Via Benevento 6 00161 Roma Italy.
Monocytes
>zoo p/l
1200 1111 Patients with > 1 infectious epysode per year Documented viral infections (n./patients) Documented bacterial infections
bacterial infections, but no statistically significantly so. The limits of these observations are evident. Some studies have indicated that automated monocyte counts (Technicon H6000) can show some imprecision in degrees. The presence of large numbers of LUC (large lymphocytes and/or blast cells) or peroxidase-deficient neutrophils can increase the monocyte count. This fact is evident in the output listing; therefore microscopic review is advised. Moreover all our evaluations are retrospective and therefore, even if carefully done, will not be randomized. In any case, we would stress that a prospective study on relationship between monocyte PB levels and infections, especially in B-CLL, could be very interesting and could better define the role of monocytopenia in the immune depression of the patient with hematologic disease.
13/18
P=O.Ol
36/89
4/18
P=0.04
5/89
11/ 18
P= NS
33/89
119
