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Biomedical subjects

H Imanaka

Publications and source records attributed to H Imanaka.

At least 37 records · Page 2Linked to original sources

Increased circulating vascular endothelial growth factor is correlated with disease activity in polyarticular juvenile rheumatoid arthritis.

OBJECTIVE: To investigate the relevance of vascular endothelial growth factor (VEGF) in the pathogenesis of juvenile rheumatoid arthritis (JRA). METHODS: Serum VEGF levels in 58 patients with JRA (systemic in 17, polyarticular in 29, pauciarticular in 12) were measured by ELISA and compared with those of 21 patients with infectious diseases and 50 healthy children. Correlations of VEGF levels with number of joints with active arthritis, erythrocyte sedimentation rate (ESR), and hyaluronic acid (HA) were examined. RESULTS: Serum levels of VEGF in patients with JRA were significantly higher than in healthy controls. Patients with systemic and polyarticular JRA showed statistically higher levels of VEGF than those with infectious diseases. VEGF levels correlated statistically with C-reactive protein (CRP) in patients with both infectious diseases and polyarticular JRA, but the regression slope (VEGF/CRP) was much steeper in polyarticular JRA than in infectious diseases. Serum VEGF levels correlated with disease activity variables such as the number of joints with active arthritis, ESR, and serum HA levels in polyarticular JRA. CONCLUSION: The correlation of serum VEGF levels and disease activity in polyarticular JRA suggests that VEGF may take an active part in joint inflammation.

Adolescent↗

Value of mild hypothermia in patients who have severe circulatory insufficiency even after intra-aortic balloon pump.

STUDY OBJECTIVE: To evaluate the effectiveness of mild hypothermia in postcardiac surgical patients with severe heart failure in spite of conventional medical therapy and the use of intra-aortic balloon pumping (IABP). DESIGN: Prospective, clinical study. SETTING: Teaching hospital. PATIENTS: 10 postcardiac surgical patients with severe heart failure despite the use of IABP with massive doses of catecholamine. INTERVENTIONS: Patients underwent mild hypothermia produced by surface cooling (to approximately 34.5 degrees C). Hemodynamic criteria for the induction of hypothermia included a cardiac index (CI) of less than 2.2 L/min/m2 with a pulmonary capillary wedge pressure (PCWP) of up to 18 mmHg despite the use of IABP with massive doses of catecholamine. MEASUREMENTS AND MAIN RESULTS: After control measurements had been taken at normal core body temperature (37 degrees C), patients were cooled to approximately 34.5 degrees C (using a cooling blanket and gastric lavage with cold water) to decrease tissue oxygen (O2) demand. Patients showed significant improvements in CI (1.9 +/- 0.3 to 2.2 +/- 0.3 L/min/m2), mixed venous O2 saturation, (SvO2; 55 +/- 7 to 64 +/- 6%), and urine output (2.1 +/- 1.1 to 3.4 +/- 2.2 ml/kg/hr). Patients were rewarmed while SvO2 was being monitored. The duration of the hypothermia was 38 +/- 41 hours. Oxygen delivery increased in 8 of the 10 patients, the mean value (+/- SD) for the group rising from 309 +/- 65 ml/min/m2 to 358 +/- 57 ml/min/m2 as temperature was reduced from 36.7 +/- 0.4 degrees C to 34.7 +/- 0.3 degrees C. All patients were successfully weaned from IABP at 140 +/- 107 hours after admission to the intensive care unit. CONCLUSIONS: Mild hypothermia is a simple and useful procedure for improving the circulation of postcardiac surgical patients with severe heart failure despite the use of IABP.

Aged↗

Cardiac surgery and inhaled nitric oxide: indication and follow-up (2-4 years).

We studied the effect of inhaled nitric oxide (NO) on 80 patients who had undergone cardiac surgery in our center. The indications for receiving NO inhalation and the number of patients were as follows: Pp/Ps > 0.5 for pulmonary hypertension (PH) (n = 32; 21 children and 11 adults), severe PH crisis (n = 9), high pulmonary vascular tone (Glenn pressure more than 18 mm Hg after bidirectional Glenn operation) or arterial oxygen saturation (SaO2) less than 70% despite an FiO2 of 1.0 after Blalock-Taussig shunt (n = 6), mean pulmonary artery pressure (PAP) > 15 mm Hg and transpulmonary gradient (TPG) (mean PAP - left atrial pressure [LAP]) > 8 mm Hg after Fontan-type operation (n = 18), elevated pulmonary vascular tone (mean PAP > 30 mm Hg and left ventricular assist system [LVAS] flow rate < 2.5 L/min/m2) in patients with LVAS (n = 3), and impaired oxygenation (PaO2/FiO2 < 100 under positive end-expiratory pressure [PEEP] > 5 cm H2O) (n = 12). Low dose inhaled NO (10 ppm) had the following effects. In adult PH patients, it significantly reduced the mean PAP (from 37.3 to 27.0 mm Hg; average values are given) and increased the mean systemic arterial pressure (SAP) (64.7 to 75.3 mm Hg). In infant PH patients, it increased the mean SAP (51.8 to 56.1 mm Hg). In patients with a PH crisis, it significantly reduced the central venous pressure (CVP) (13.3 to 8.8 mm Hg) while increasing both the mean SAP (49.4 to 57.9 mm Hg) and PaO2/FiO2 (135 to 206). In patients after a Fontan-type operation, it significantly reduced the mean PAP (16.8 to 13.8 mm Hg) and TPG (9.5 to 5.8 mm Hg). In patients under LVAS, it reduced the CVP (11.7 to 8.0 mm Hg) and mean PAP (32.0 to 24.7 mm Hg). In impaired oxygenation patients, PaO2/FiO2 was increased (75 to 106). Sixty-five patients were all followed for 2.0-4.3 years (average, 3.1 years). All 65 patients remained free from oxygen requirement, and possible chronic adverse effects including the occurrence of malignant tumors or chronic inflammation in the respiratory tract were not observed.

Administration, Inhalation↗

Expiratory phase and volume-adjusted tracheal gas insufflation: a lung model study.

OBJECTIVE: To evaluate in a lung model the effects of expiratory-phase tracheal gas insufflation (expiratory-phase TGI) with both volume and pressure control ventilation, and tidal volume-adjusted continuous flow TGI (volume-adjusted TGI) on system pressures and volumes. DESIGN: Single-compartment lung model. SETTING: Research laboratory in a university medical center. INTERVENTIONS: Expiratory-phase TGI was established, using a solenoid valve activated by the ventilator. Volume-adjusted TGI was applied by reducing tidal volume (VT) by the product of TGI flow and inspiratory time. Ventilation was provided with pressure control of 20 cm H2O or volume control ventilation with VT similar to that with pressure control ventilation. A rate of 15 breaths/min and positive end-expiratory pressure (PEEP) of 10 cm H2O were used throughout. Inspiratory time periods of 1.0, 1.5, 2.0, and 2.5 secs were used with TGI flows of 0, 4, 8, and 12 L/min. Lung model compliance (mL/cm H2O) and resistance (cm H2O/L/sec) combinations of 20/20, 20/5, and 50/20 were used. MEASUREMENTS AND MAIN RESULTS: In expiratory-phase TGI with pressure control ventilation, peak alveolar pressure remained constant, PEEP increased (p < .01) and VT decreased (p < .01). In expiratory-phase TGI with volume control ventilation and volume-adjusted TGI, there were significant increases in peak alveolar pressure and PEEP (p < .01). Readjustment of VT in volume-adjusted TGI was impossible with longer inspiratory time (> or = 2 secs) and higher TGI flows (> or = 8 L/min). CONCLUSIONS: The marked increases in system pressures and volumes observed with continuous-flow TGI can be avoided with expiratory-phase TGI and volume-adjusted TGI.

Insufflation↗

Effects of pressure-support ventilation on recovery from acute diaphragmatic fatigue in rabbits.

OBJECTIVES: To examine the effects of pressure-support ventilation on recovery from acute diaphragmatic fatigue. DESIGN: Prospective laboratory trial. SETTING: Experimental laboratory. SUBJECTS: Twenty-one healthy, adult New Zealand white rabbits. INTERVENTIONS: Diaphragmatic fatigue was induced with 50-Hz phrenic nerve stimulation for 30 mins. Recovery was compared between pressure-support ventilation 0 cm H2O (SB), 10 cm H2O (P10), and 20 cm H2O (P20) for 90 mins immediately after the end of the fatigue inducing procedure. MEASUREMENTS AND MAIN RESULTS: After the fatigue-inducing procedure, pressure-support ventilation reduced transdiaphragmatic pressure and integrated diaphragmatic electromyogram both at P20 and P10, but not in SB. Recovery was assessed by airway occlusion pressure (Poccl) generated by high- (100 Hz) and low- (20 Hz) frequency phrenic nerve stimulation. Poccl at 100 Hz was lower in P10 and P20 than in SB (74.6 +/- 6.2 [SEM] %, 66.9 +/- 3.3%, and 94.8 +/- 3.6% of the baseline at 90 mins for P10, P20, and SB, respectively), while those at 20 Hz showed no differences between the three groups. CONCLUSION: Recovery from acute diaphragmatic fatigue might be disturbed with pressure-support ventilation.

Animals↗

Transient low T cell response to streptococcal pyrogenic exotoxin-C in patients with Kawasaki disease.

Superantigens (SAs) are known to induce transient anergy followed by T cell activation. Recent reports have suggested that SAs are involved in the pathogenesis of Kawasaki disease (KD). In the present study, we investigated the peripheral T cell response to SAs by measuring proliferation and IL-2 production to determine whether the T cell anergy is induced by SAs in patients with KD. T cells were obtained from 45 Japanese patients with KD in different stages of the disease and were stimulated by streptococcal pyrogenic exotoxin (SPE)-A, SPE-C, and toxic shock syndrome toxin-1 (TSST-1). T cells from patients with KD in the acute or convalescent stage up to 2 mo showed significantly lower proliferation and IL-2 production than did T cells from healthy control subjects stimulated by SPE-C, but not SPE-A or TSST-1. The T cell response to SPE-C normalized within 1 y. The low T cell response to SPE-C in the acute stage correlated with a peak platelet count and the C-reactive protein-positive period. These findings suggest that the transient low T cell response to SPE-C in patients with KD may have been related to SA-induced anergy or disappearance of SPE-C-responding cells from the circulation. The present results suggested that SPE-C may be involved in the pathogenesis of KD.

Acute Disease↗

[A case of central sleep-apnea syndrome accompanied by bilateral paralysis of the diaphragma after pediatric cardiac surgery].

Sleep-apnea syndrome is a serious problem in respiratory care. Considerable attention has been paid to it, because it sometimes produces severe hypoxia and hypercapnia, and can cause death. We present a case of a six-year-old girl who showed sleep-apnea syndrome. She suffered from bilateral paralysis of the diaphragm after cardiac surgery and had to be managed under mechanical ventilation for three months. When weaning was tried from mechanical ventilation, she frequently showed apnea lasting over 15 seconds at night, and she was diagnosed as having sleep apnea. She was medicated with theophylline to stimulate the so-called respiratory center. Next day she was successfully weaned from mechanical ventilation. After she had been weaned from mechanical ventilation, hypoxia, hypercapnia, and tachycardia were detected by respiratory monitor at night. The respiratory monitor enabled us to identify the clinical appearance of sleep-apnea, and theophylline may have contributed to its improvement.

Cardiac Surgical Procedures↗

Nitric oxide (NO) measurement accuracy.

BACKGROUND: Evaluation of the clinical utility of NO requires accurate assessment of inspired [NO]. Currently, chemiluminescence analyzers are the clinical standard for analysis; however, their performance in the clinical setting has not been systemically evaluated. METHODS: We evaluated the performance of four chemiluminescence analyzers (270B NOA, Sievers Instruments, Inc.; CLA 510S, Horiba Co., Ltd.; CLD 700 AL, Eco Physics Corp.; Model 42, Thermo Environmental Instruments Inc.) in simulated clinical settings. Transport delay and dynamic 95% response time were measured by the balloon in a glass chamber puncture technique. Fluctuating [NO] in a continuous flow of gas and [NO] during mechanical ventilation, where NO was premixed prior to entering the ventilator, were evaluated. RESULTS: Transport delay ranged from 1.02 +/- 0.02 to 24.36 +/- 2.47 s (p < 0.05) and the 95% response time ranged from 0.22 +/- 0.04 to 70.03 +/- 0.03 s (p < 0.05). Accurate analysis of [NO] in a continuous flow system was only possible with the most rapid response analyzer (270B NOA). All other analyzers under reported the maximum [NO] (p < 0.05) and over reported the minimum [NO] (p < 0.05). All analyzers accurately determined [NO] in the inspiratory limb of the ventilator circuit, but none accurately determined [NO] at the airway opening. CONCLUSIONS: Measurements of inhaled [NO] can vary greatly, dependent upon the performance characteristics of the analyzer and the location of NO analysis. All studies evaluating the clinical use of NO should fully describe the technical gas delivery methodology and the response time and transport delay of the chemiluminescence analyzer used.

Administration, Inhalation↗

Assessment of errors when expiratory condensate PCO2 is used as a proxy for mixed expired PCO2 during mechanical ventilation.

OBJECTIVES: We designed a series of experiments to determine whether expiratory water condensate (PconCO2) can be used as a proxy for mixed expired gas collection. METHODS: In 18 adult mechanically ventilated patients with ARDS (40 samples), simultaneous collections of arterial blood, expiratory water trap condensate, mixed expired gas, and minute ventilation were used to calculate VCO2 and VD/VT. To assess the effect of temperature, a constant gas flow (PCO2 10-30 mm Hg) was bubbled through water at temperatures of 19.5-37 degrees C. Gas and water samples were collected, immediately analyzed for PCO2, and a temperature correction factor was calculated. A lung model was constructed using a 5 L anesthesia bag connected to a mechanical ventilator with a heated humidifier. Temperature at the Y-piece was set to approximately 37 degrees C and CO2 was injected into the bag to establish an end-tidal PCO2 of 20-70 mm Hg. After equilibration, condensate was collected, PCO2 was measured, and the temperature-corrected PCO2 was compared to PECO2. The capnogram at points along the expiratory limb circuit was used to evaluate gas mixing. RESULTS: There was an over-estimation of PECO2 by PconCO2 (p < 0.001) for the patient data, resulting in an underestimation of VD/VT (p < 0.001) and an overestimation of VCO2 (p < 0.001). The temperature correction factor for PCO2 in water was -0.010 (about half of the factor used for whole blood). The bias between temperature-corrected PconCO2 and PECO2 was 0.3 +/- 3.2 mm Hg in the lung model. Mixing in the expiratory limb was poor, as evaluated by the capnogram. CONCLUSIONS: Even with temperature correction, we failed to precisely predict PECO2 from PconCO2. For measurement of VD/VT and VCO2, we do not recommend methods that use PconCO2.

Adult↗

Ocular surface disorders in the critically ill.

Abnormalities of the cornea and conjunctiva occur in association with neurological diseases, nocturnal lagophthalmos, coma, infection, and mechanical ventilation. We investigated the incidence and causes of ocular surface disorders in critically ill patients. In a retrospective study, the presence of conjunctivitis and corneal erosion was determined by reviewing the medical charts of 143 mechanically ventilated patients (intensive care unit [ICU] stay > or =7 days). In the subsequent prospective study, 15 patients who had sedatives or muscle relaxants administered continuously for more than 48 h in the ICU were investigated. Corneal erosion was examined using a slit lamp once a day. Ocular surface disorder was found in 28 of the 143 patients (20%) whose ICU stay exceeded 7 days. The incidence increased with continuous sedation (35% vs 15%). The incidence also increased with continuous neuromuscular blockade (39% vs 11%). In the prospective study, nine patients (60%) developed corneal erosion. A patient's inability to fully close his or her eyes increased the incidence (P < 0.01) of corneal erosion. Protective eyelid taping was effective in preventing and treating the corneal erosion. In conclusion, the critically ill often develop ocular surface disorders, especially when sedated and immobilized. A close relationship was observed between these conditions and the inability to close one's eyes.

Adolescent↗

Inaccuracies of nitric oxide delivery systems during adult mechanical ventilation.

BACKGROUND: Various systems to administer inhaled nitric oxide (NO) have been used in patients and experimental animals. We used a lung model to evaluate five NO delivery systems during mechanical ventilation with various ventilatory patterns. METHODS: An adult mechanical ventilator was attached to a test lung configured to separate inspired and expired gases. Four injection systems were evaluated with NO injected either into the inspiratory circuit 90 cm proximal to the Y piece or directly at the Y piece and delivered either continuously or only during the inspiratory phase. Alternatively, NO was mixed with air using a blender and delivered to the high-pressure air inlet of the ventilator. Nitric oxide concentration was measured from the inspiratory limb of the ventilator circuit and the tracheal level using rapid- and slow-response chemiluminescence analyzers. The ventilator was set for constant-flow volume control ventilation, pressure control ventilation, pressure support ventilation, or synchronized intermittent mandatory ventilation. Tidal volumes of 0.5 l and 1 l were evaluated with inspiratory times of 1 s and 2 s. RESULTS: The system that premixed NO proximal to the ventilator was the only one that maintained constant NO delivery regardless of ventilatory pattern. The other systems delivered variable NO concentration during pressure control ventilation and spontaneous breathing modes. Systems that injected a continuous flow of NO delivered peak NO concentrations greater than the calculated dose. These variations were not apparent when a slow-response chemiluminescence analyzer was used. CONCLUSIONS: NO delivery systems that inject NO at a constant rate, either continuously or during inspiration only, into the inspiratory limb of the ventilator circuit produce highly variable and unpredictable NO delivery when inspiratory flow is not constant. Such systems may deliver a very high NO concentration to the lungs, which is not accurately reflected by measurements performed with slow-response analyzers.

Adult↗

Unloadiing of the work of breathing by proportional assist ventilation in a lung model.

OBJECTIVES: Proportional assist ventilation is devised to increase airway pressure in proportion to inspiratory effort. A systematic study of the performance of this new mode of ventilation has not been presented. We tested in the laboratory the capability of proportional assist ventilation to unload the work of breathing in proportion to ventilatory drive, under a variety of mechanical loads. DESIGN: During variations of "ventilatory drive" (i.e., tidal volume), unloading of the work of breathing by proportional assist ventilation was contrasted with unloading by pressure-support ventilation. SETTING: The respiratory laboratory of a university-affiliated teaching hospital. SUBJECT: A bellows-in-a-box lung model, powered by a sine wave air flow generator. INTERVENTIONS: Proportional assist and pressure-support ventilation were preset to provide comparable support at a baseline "ventilatory drive" of 0.7-L tidal volume. The set levels of proportional assist and pressure-support ventilation were subsequently applied to five tidal volumes, from 0.2 to 1.2 L. Three levels of inspiratory support and three settings of mechanical load were evaluated. MEASUREMENTS AND MAIN RESULTS: Proportional assist ventilation significantly (p < .05) reduced the work of breathing of the lung model at all but the lowest tidal volume (0.2 L). The preset proportion of ventilatory support (30%, 50%, and 70%) unloaded the work of breathing uniformly as ventilatory drive was varied at tidal volumes of > or = 0.5 L, but not always at tidal volumes of < or = 0.4 L. In contrast, pressure-support ventilation overassisted low tidal volumes and underassisted high tidal volumes (p < .05). CONCLUSIONS: In a lung model, a prototype system delivering proportional assist ventilation provided uniform unloading of the work of breathing as the ventilatory drive was varied within a tidal volume range of 0.5 to 1.2 L. These findings confirm the theoretical modeling of proportional assist ventilation. This system, however, failed to properly unload low tidal volumes of 0.2 to 0.4 L.

Humans↗

Clinical features of Japanese children and adolescents with systemic lupus erythematosus: results of 1980-1994 survey.

Marked advances have been made in the past decade in the management of adults with systemic lupus erythematosus (SLE). Therefore, a nationwide retrospective survey was conducted between 1980 and 1994 to investigate the clinical manifestations of SLE in Japanese children and adolescents. Questionnaires were sent to 340 hospitals. Of 405 patients reported by 176 hospitals, 373 patients, diagnosed by the criteria established by the Pediatric Study Group of the Japanese Ministry of Health and Welfare in 1985, were enrolled in the study. Forty-nine of the 354 patients (13.8%) had relatives with a connective tissue disease within the third degree of consanguinity. The frequent manifestations in 373 patients were the presence of antinuclear antibody (98.9%), immunologic disorders (93.0%), hypocomplementemia (87.1%), malar rash (79.6%) and fever (74.0%). Lupus nephritis was present in 148 of the 309 patients (47.9%) at their first visit to a clinic, and 261 of the 373 patients (70.0%) developed renal involvement during the observation period. Of 370 patients, 92 patients (24.9%) exhibited central nervous system lupus. Of 368 patients, 192 patients (52.2%) were treated by methylprednisolone pulse therapy and 148 patients (40.2%) received immunosuppressants in combination with steroid therapy at some stage during the observation period, Survival rate at 5 years from onset was 95.9%. Management of infection, coagulopathies, and central nervous system involvement is essential to improve the prognosis of SLE in Japanese children and adolescents.

Adolescent↗

Recovery of diaphragmatic function in awake sheep after two approaches to thoracic surgery.

Video-assisted thoracoscopic surgery (VATS) is replacing thoracotomy, but no study has addressed the extent or duration of VATS-induced diaphragmatic alteration. We hypothesized that VATS would impair diaphragmatic function less and return diaphragmatic function faster than thoracotomy. In eight sheep, sonomicrometers were randomly implanted on the right costal diaphragm via VATS or thoracotomy. Diaphragmatic resting length, shortening fraction, and respiratory function were measured weekly during quiet breathing (QB) and CO2 rebreathing for 4 wk. For VATS, shortening fraction was smallest on postoperative days 1 (POD 1) (6.4 +/- 3.4 and 12.9 +/- 8.7% during QB and 10% CO2 rebreathing, respectively) and 7 (6.3 +/- 3.4 and 16.9 +/- 4.0% during QB and 10% CO2 rebreathing, respectively) and recovered by 3 wk (13.2 +/- 1.8 and 28.9 +/- 8.0% during QB and 10% CO2 rebreathing, respectively). For thoracotomy, shortening fraction at 10% CO2 rebreathing was smaller on PODs 1, 7, 14 (15.9 +/- 7.1, 13.6 +/- 5.4, and 19.0 +/- 6.9%) than on POD 28 (29.9 +/- 8.2%), but not during QB on POD 1 or 7 (7.5 +/- 3.8 and 3.4 +/- 2.6%) compared with POD 28 (10.7 +/- 8.7%). Shortening fraction did not differ between surgeries. There was no group difference in minute ventilation, respiratory rate, transdiaphragmatic pressure, or esophageal and gastric pressures. In conclusion, although shortening fraction recovered faster for VATS, this translated into insignificant functional differences.

Animals↗

Performance characteristics of bilevel pressure ventilators: a lung model study.

Bilevel pressure ventilators are being used increasingly to provide noninvasive ventilatory support in the management of obstructive sleep apnea, chronic ventilatory failure, and acute respiratory failure. However, the ability of these ventilators to respond to inspiratory demand without imposing expiratory loads has not been evaluated extensively. We evaluated the performance of nine bilevel pressure ventilators in a lung model, as compared with the Nellcor Puritan-Bennett 7200ae adult critical care ventilator. All ventilators were set to provide pressure support ventilation (PSV) and positive end-expiratory pressure (PEEP) at a rate of 10 breaths/min with an inspiratory time of 1.0 s. Simulated pleural pressure, airway pressure, and flow at airway opening were continuously monitored. We studied the effects of three PSV levels (5, 10, and 15 cm H2O) with 5 cm H2O PEEP at two lung compliances (50 and 80 mL/cm H2O) and four peak inspiratory flow demands (20, 40, 60, and 80 L/min) on seven dependent variables: inspiratory delay time (D-I), inspiratory trigger pressure (P-I), inspiratory area percent (Area I%), expiratory delay time (D-E), supraplateau expiratory pressure change (P-E), expiratory area (Area E), and ventilator peak flow (VPF). Most ventilators performed as well as or significantly (p<0.05) better than the 7200ae in all studied variables. Compliance did not significantly affect ventilator performance. Increasing inspiratory flow demand significantly (p<0.05) increased D-I, P-I, P-E, and VPF and decreased Area I% with most ventilators. As ventilatory demand increased, D-E and Area E significantly (p<0.05) changed. With some units, D-E and Area E increased, while with others they decreased. Most bilevel pressure ventilators evaluated were able to respond to high ventilatory demands and outperformed the Nellcor Puritan-Bennett 7200ae ventilator.

Calibration↗

[Two cases with SLE and MCTD developed after a long period of chronic arthritis that was initially diagnosed as JRA].

In order to discuss the diversity of clinical features and the difficulty in diagnosis of children with juvenile rheumatoid arthritis (JRA), we present two cases who have documented the development of systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD) after a long period of disease characterized only by arthritis that was initially diagnosed as JRA. The first case was a girl diagnosed for her arthritic joints as polyarticular JRA at 15 years of age. At onset, she had Raynaud phenomenon but autoantibodies such as anti-nuclear antibody (ANA), anti-DNA antibody, and rheumatoid factor were negative. Five years after onset, she became ANA positive and 3 years later she became pregnant. During her pregnancy, she became positive for anti-DNA antibody without any signs of nephritis. One month after the delivery, however, she developed butterfly rash, carditis, nephritis, and was diagnosed as SLE. No destructive changes were observed in her joints though arthritis continued for 8 years form onset to pregnancy. The second case was a 3 years old girl who was diagnosed as polyarticular JRA. Treatment by aspirin induced complate remission after one year from the onset. However, 10 years after that remission, she developed Raynaud phenomenon and arthralgia in her knees and hip joints. Her laboratory findings showed hypergammaglobulinemia, positive ANA, positive anti-DNA antibody, positive anti-RNP antibody. She was eventually diagnosed as MCTD when she was found to have polymyositis by EMG and serum CK. In the present paper, two cases imply the difficulty in diagnosing JRA and diversity of rheumatic diseases such as JRA, SLE and MCTD. Closer and longer period of observation is essential for the JRA patients with nondestructive arthritis.

Adolescent↗