Measurement of subgroups of peripheral blood T lymphocytes in patients with severe acute respiratory syndrome and its clinical significance

Objective To investigate the changes of subgroups of peripheral blood T lymphocytes in patients with severe acute respiratory syndrome (SARS) and its clinical significance.Methods Subgroups of blood T lymphocytes in 93 patients with SARS were detected by flow cytometer. The results detected in 64 normal subjects and 50 patients with AIDS served as controls.Results The numbers of CD3 +, CD4 +, and CD8 + lymphocytes all significantly decreased in acute phase of patients with SARS [(722±533)/μl, (438 ±353)/μl, (307±217)/μl)] compared with those in normal controls [ (1527±470)/μl, (787±257)/μl, (633±280)/μl, all P<0. 01) ], which was different from what we observed in patients with AIDS who had decreased CD4 + [ (296±298)/μl] but increased CD8 + [ (818 ±566)/μl counts. The counts of CD3+, CD4+, and CD8 + lymphocytes decreased more apparently in patients with severe SARS. All the five patients who died had CD4 + counts less than 200/μl. As the patients' condition improved, CD3 +, CD4 +, and CD8 + counts gradually returned to normal ranges.Conclusion The damage of cellular immunity is probably an important mechanism of pathogenesis of SARS.

Dynamic changes in blood cytokine levels as clinical indicators in severe acute respiratory syndrome

Objective To investigate the dynamic changes observed in serum levels of interleukins (ILs), tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1 ) in severe acute respiratory syndrome (SARS) patients.Methods Sixty-one cases of SARS with positive antibodies to SARS coronavirus (SARS-CoV) were classified into the following categories: initial stage (3-7 days), peak stage (8-14 days), and remission and recovery stage (15 -27 days). Forty-four healthy individuals were used as controls. Serum levels of ILs, TNF-a and TGF-p, were measured in all subjects. Serum antibodies to SARS-CoV were detected only in SARS cases.Results The mean concentration of serum IL - 6 in SARS patients did not differ from that in the control group in initial and peak stages, but became significantly higher in remission and recovery stage compared with the control group, initial and peak stages ( P<0. 01). The mean concentration of serum IL-8 in SARS patients did not differ from that of the control group in initial stage, but was significantly higher than control group in peak stage and remission and recovery stage ( P < 0. 05). And it was more significantly higher in remission and recovery stage than in peak stage ( P<0. 01). The mean concentrations of IL-16 and TNF-αin SARS patients were higher than those of the control group for every length of the clinical courses investigated, and were especially high in remission and recovery stage (P<0. 01). SARS patients experienced higher concentration of serum IL-13 compared with the controls in initial stage ( P < 0. 01), but returned to normal levels in peak stage and in remission and recovery stage. The mean concentration of serum IL-18 in SARS patients was significantly lower than that of the control group during all clinical courses ( P < 0. 05). The mean concentration of serum TGF-β1, in SARS patients was higher than that of the control group during all clinical courses. Although TGF-bbbbb1 in serum decreased in remission and recovery stage in SARS patients, the average was still higher than that of the control group (P<0. 01). Conclusions Most proinflammatory cytokines and TGF-β1, were elevated during the early phase of SARS, which may be associated with lung infiltration and proliferation. Concurrently, the mean concentration of serum IL-13 decreased gradually, and the mean concentration of serum IL-18 level in SARS patients was lower than that of the control group during all the courses of SARS, suggesting that the immune state of the patients with SARS was obviously abnormal. Observing the dynamic changes in blood cytokine levels can provide a scientific basis to assess pathogenesis and efficacy of clinical treatment of SARS.

A retrospective study of 78 patients with severe acute respiratory syndrome

Objective To summarize the clinical features of severe acute respiratory syndrome (SARS) and to discuss diagnosis and management of the disease.Methods A retrospective study was conducted on 78 cases of SARS referred to the Guangzhou Institute of Respiratory Diseases (GIRD) between December 22, 2002 and near the end of March 2003. Items reviewed cover all data concerning clinical manifestations, laboratory investigation and radiology.Results The patients in the study consisted of 42 males and 36 females, aged 20 -75 yrs (mean age 37. 5±11. 6 yrs), including 44 affected health-care professionals. Clinical symptoms seen in the group were fever (100.0%), cough (88.5%), and dyspnea (79.5%). There were 12 cases (15. 3%) with WBCs <4. 0 x109/L, 49 cases (62. 8%) ranging between (4. 0-10. 0) ×10~9/L and 17 cases (21. 8%) over 10. 0×10~9/L. The average was(7. 58 ?. 96) x 109/L, with 0. 75±0.14 (neutrophil) and 0.18±0.11 (lymphocyte). Chest films and CT scanning revealed changes related to pneumonia. The transmission of the disease was likely via close contact with contagious droplets. The prevalences of acute lung injury (ALI, in 37cases) and acute respiratory distress syndrome (ARDS, 21 out of 37 cases) were considerably high among the patients. Seven patients who developed ARDS complicated with multiple organs dysfunction syndrome (MODS) died.Conclusions A history of close contact, fever, sign of pneumonia by X-ray and normal-to-lowered WBC counts are favorable for the diagnosis of SARS. Recognition of ALI as the important index for critical SARS and comprehensive supportive management are of paramount in decreasing the mortality of the disease.

Clinical analysis of 45 patients with severe acute respiratory syndrome

Objective To explore the clinical and radiological features of severe acute respiratory syndrome (SARS).Methods Analysis of the clinical presentation, chest radiographs, course of disease and features of severe pneumonia in 45 SARS patients diagnosed at our hospital in Beijing between April 5 - 20, 2003. Also included is a summation of the clinical features of SARS.Results (1) SARS appears to have high infectivity; (2) the most common symptom is fever; (3) the count of leukocyte is normal or decreased; (4) most patients (35/45, 77.8%) had experienced a 24-hour fever prior to the abnormal chest X-ray changes which showed progression of pulmonary infiltrates within 48 hours in 71.1% (32/45) of the patients and, (5) the percentage of patients who developed severe pneumonia (24. 4%) is higher than those who developed typical pneumonia.Conclusion SARS is a disease with high infectivity and has its own clinical and radiological features. Early recognition, prompt isolation, and appropriate therapy are the key to combate this infection.