Leukemoid reaction: spectrum and prognosis of 173 adult patients.

BACKGROUND: The prognosis of patients with leukemoid reaction (LR) depends mainly on their underlying illness. Our aim was to investigate the etiologies and prognosis of a mixed group of patients with LR. METHODS: We identified 173 patients who had ≥30.0 × 10(9) leukocytes/µL without hematologic malignancies. Causes of LR and factors contributing to death were analyzed. RESULTS: Patients with LR constituted 0.59% of all admitted adults. The median age was 75 years, but 20 patients were aged <40 years. There was no difference in LR prevalence by gender (female/male = 88/85). Average white blood cell (WBC) count was 37.7 × 10(9)/µL. Fourteen patients (8.0%) had a WBC count of >50.0 × 10(9)/µL. The median duration of LR was 1 day, but 39 patients had prolonged LR (>1 day). Infection was the most common cause of LR (n = 83, 47.9%; 95% confidence interval, 40.7-55.4), followed by ischemia/stress (27.7%), inflammation (6.9%), and obstetric diagnoses (6.9%). Higher WBC counts were significantly associated with positive blood cultures (P = .017) or a positive Clostridium difficile toxin (P = .001). Antibiotics were prescribed for 140 patients (80.9%). Sixty-six patients (38.1%) died during hospitalization. Those with prolonged LR had an in-hospital mortality rate of 61.5%. Factors found to be highly correlated with death were age (odds ratio [OR] = 1.051, P < .001), any infectious diagnosis (OR = 2.574, P = .014), and sepsis (OR = 3.752, P = .001). CONCLUSIONS: LR carries a grave prognosis, especially among the elderly and those with sepsis. LR was found to have multiple etiologies including infections, stress, inflammation, and obstetric diagnoses.

Renal abscess with Morganella morganii complicating leukemoid reaction.

We report a case of leukemoid reaction (LR) complicating renal abscess caused by Morganella morganii infection in an 80-year-old man. On administration, laboratory tests revealed white blood cell count of 76160 /microL and C reactive protein 3.09 mg/dL. Although chronic myeloid leukemia was suspected, bcr/abl fusion transcript was not observed. Contrast enhanced computer tomography imaging of the abdomen showed abscess in the right kidney. M. morganii was detected repeatedly in material of liquid from the abscess and arterial blood culture. To our knowledge, this is the first case of M. morganii infection complicating LR.

The leukemoid reaction in Clostridium sordellii infection: neuraminidase induction of promyelocytic cell proliferation.

Life-threatening Clostridium sordellii infections have recently been reported in women undergoing therapeutic abortion, during natural childbirth, and in injection drug users. Shock, diffuse capillary leak, and a leukemoid reaction (LR) are cardinal features of these infections. The magnitude of the LR is highly correlated with mortality. We have isolated a 42-kDa extractable protein from C. sordellii culture supernatant that stimulates proliferation of promyelocytic HL-60 cells in vitro. Using mass spectrometry, we have identified this protein as the C. sordellii neuraminidase, NanS. Recombinant NanS (rNanS) dose dependently stimulated HL-60 cell proliferation. Increased proliferation was observed when HL-60 cells were cocultured with both rNanS and granulocyte-macrophage colony stimulating factor. In addition, NanS also modified vascular cell adhesion molecule 1, which orchestrates the release of mature and immature granulocytes from bone marrow stromal cells. Thus, neuraminidase likely plays an important role in the characteristic LR in C. sordellii infection.

Disseminated hepatosplenic mycobacterial infection masking myeloproliferative diseases as leukemoid reaction: a diagnostic pitfall.

The distinction of myeloproliferative disease (MPD) from leukemoid reactions due to reactive causes can be difficult. In the presence of simultaneous occurrence of MPD and an established infection, only the demonstration of a clonal marker or prolonged observation can substantiate the diagnosis. We present three cases of MPD presenting as leukemoid reaction due to disseminated hepatosplenic mycobacterial sepsis. There appeared to be an association between MPD and reduced resistance to mycobacterial infection. Clinicians and hematologist should be aware of such a predisposition and possible dual pathology for proper diagnosis, therapy and monitoring of both the infection and the myeloproliferation.

Cytokines in the stools of children with complicated shigellosis.

The pathogenesis of the systemic complications, leukemoid reaction and hemolytic uremic syndrome, associated with Shigella dysenteriae type 1 infection is not well understood. The excessive production of proinflammatory cytokines, including tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6), has been suggested as a possible factor. We measured IL-6 and TNF-alpha in stools of 56 children with S. dysenteriae 1 infection and 29 children without any apparent infection, all age 12 to 60 months. Sixteen children with S. dysenteriae 1 infection had leukemoid reaction or hemolytic uremic syndrome (complicated shigellosis), while the others did not (uncomplicated shigellosis). Stool IL-6 and TNF-alpha concentrations were higher in children with uncomplicated shigellosis than in children with complicated shigellosis (P = 0.009 and < 0.001, respectively) or in uninfected children (P < 0.001). It is concluded that complicated infection is not associated with higher concentrations of the proinflammatory cytokines IL-6 and TNF-alpha in stool.