Single high-dose intravenous immunoglobulin therapy for kawasaki disease increases plasma viscosity

The use of intravenous immunoglobulin in the treatment of Hashimoto's encephalopathy: case based review

Background

Hashimoto's encephalopathy (HE) is a controversial immunological neuropsychiatric disease, with a poorly understood pathogenesis. It is characterized by symptoms of acute or subacute encephalopathy which usually occur in the presence of elevated levels of antithyroid antibodies. Even though it is also known as steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT), some cases appear to be steroid-resistant. This review examined whether treatment of Hashimoto's encephalopathy with intravenous immunoglobulin (IVIG) is associated with better clinical outcomes than the standard therapy. Additionally, we presented a case of a 59-year-old man who presented with severe neurological manifestations and was successfully treated with intravenous immunoglobulin.

Methods

The online databases PubMed and EMBASE were searched.

Results

A total of 1,365 articles were identified. After the deletion of 112 duplicates, 1,253 studies were screened by evaluating the title and abstract, focusing on Hashimoto's encephalopathy cases where IVIG were used. 846 studies were excluded because they were not relevant to the topic or included pediatric population. Therefore, 407 full-text articles were assessed for eligibility. The final analysis included 14 eligible articles after 393 were excluded (irrelevant texts, not written in English, full-text not available). In the majority of the selected case-reports, IVIG was associated with a good outcome, sometimes even with dramatic improvements in patient's status.

Conclusion

In last years, intravenous immunoglobulin therapy proved its utility in Hashimoto's encephalopathy's treatment, being a well tolerated therapy associated with remarkable improvement in patient's status. Further research is still needed in order to define the optimal treatment protocol for Hashimoto's encephalopathy and to establish if intravenous immunoglobulin can also be used as a first-line therapy, alone or in combination with steroids.

Relationship between Body Composition and Serum Immunoglobulin Concentrations after Administration of Intravenous Immune Globulin-Preclinical and Clinical Evidence

The purpose of this study was to investigate the effect of obesity on immunoglobulin G (IgG) pharmacokinetics in a rat model of obesity, and to collect clinical evidence for an association between the body composition and intravenous immune globulin (IVIG) pharmacokinetic parameters in humans. In a preclinical study, pharmacokinetics of human IgG was evaluated after intravenous (IV) and subcutaneous (SC) delivery to obese and lean rats (n = 6 in each group). Serial serum samples were analyzed using an ELISA. The animal body composition was assessed using computer tomography. Patients with primary immunodeficiency currently managed with IVIG, and at a steady state, were enrolled in the clinical study (n = 8). Serum immune globulin (Ig) concentrations were measured at baseline and immediately after the administration of two consecutive treatments, with an additional measurement at two weeks after the first administration. In addition to the patient demographic and clinical characteristics, body composition was measured using bioelectrical impedance analysis. The pharmacokinetics of human IgG was significantly different between the obese and lean rats after both the IV and SC administration of 0.5 g/kg. Furthermore, a significant difference in endogenous rat IgG was observed between the two strains. In the human study, total serum IgG and subtype (IgG1, IgG2, IgG3, IgG4) half-life negatively correlated with the body mass index and fat mass. The mean change in the total serum IgG concentration was significantly correlated to body mass index and fat mass. The results of the studies corroborated one another. In the animal study, most pharmacokinetic parameters of human IgG following IV and SC administration were significantly affected by obesity and changes in the body composition. In the clinical study, the mean serum IgG change after the IVIG administration strongly correlated to the BMI and body fat mass. Future studies are needed to establish the outcomes achieved with more frequent dosing in obese individuals with primary immunodeficiency.

NT-proBNP Levels Following IVIG Treatment for Multisystem Inflammatory Syndrome in Children

BACKGROUND

N-terminal of pro-brain natriuretic peptide (NT-proBNP) and C-reactive protein (CRP) levels are often elevated in Multisystem Inflammatory Syndrome in Children (MIS-C) secondary to inflammation, myocardial dysfunction, or increased wall tension. Intravenous Immunoglobulin (IVIG), accepted treatment for MIS-C, may transiently increase myocardial tension and contribute to an increase in NT-proBNP.

OBJECTIVE

We sought to study the association between pre- and post-IVIG levels of NT-proBNP and CRP and their clinical significance.

METHODS

This single center retrospective cohort study included consecutive children, ages ≤ 21 years, with diagnosis of MIS-C who received IVIG from April 2020 through October 2021. Data collection included clinical characteristics, laboratory tests, management, and outcomes. Study cohort consisted of patients who received IVIG and had NT-proBNP levels available pre- and post-IVIG.

RESULTS

Among 35 patients with MIS-C, 30 met inclusion criteria. Twenty-four, 80%, showed elevation in NT-proBNP post-IVIG. The median NT-proBNP level pre-IVIG was 1,921 pg/mL (IQR 548, 3,956), significantly lower than the post-IVIG median of 3,756 pg/mL (IQR 1,342, 7,634)) (p=0.0010). The median pre-IVIG CRP level was significantly higher than the post-IVIG level (12 mg/dL vs 8 mg/dL, p= 0.0006). All but one recovered prior to discharge, and none had signs of worsening cardiac function post-IVIG. In those who recovered, NT-proBNP had normalized by discharge or 1-week follow-up.

CONCLUSIONS

Our study shows that NT-proBNP levels often transiently increase immediately after IVIG therapy without signs of worsening myocardial function. These values should be interpreted in the context of CRP levels and clinical recovery.

Randomized trial of different initial intravenous immunoglobulin regimens in Kawasaki disease

BACKGROUND

We aimed to assess the efficacy of different initial intravenous immunoglobulin (IVIG) regimens in Kawasaki disease (KD) patients to find more cost-effective therapy options.

METHODS

A multicenter, open-label, blind-endpoint randomized controlled trial was conducted from January 2014 to December 2015. Patients with KD, within 10 days of illness, were randomly assigned to receive different IVIG regimens (Group A, 2 g/kg once; Group B, 1 g/kg for 2 consecutive days; Group C, 1 g/kg once) and aspirin 30mg/kg/d. Primary outcomes included hours to defervescence and development of coronary artery lesions during the study period. Major secondary outcomes included total fever days, total dose of IVIG, changes of laboratory data, length of stay, and hospitalization expenses. (ClinicalTrials.gov: NCT02439996).

RESULTS

A total of 404 patients underwent randomization. No difference was found in the outcomes of defervescence among three groups at 6, 12, 24, and 36 hours after completion of initial IVIG infusion. There were no differences in the incidence of coronary artery lesions during the study period (at week 2, month 1, month 3, and month 6 of illness), changes of laboratory data, total fever days, and length of stay. Group C patients had the lowest total dose of IVIG (mean: 1.2 vs 2.2 vs 2.1 g/kg; P < 0.001) and hospitalization expenses (mean: 8443.8 vs 10798.4 vs 11011.4 Chinese Yuan; P < 0.001) than other two groups.

CONCLUSIONS

A single dose of 1g/kg IVIG is a low-cost treatment with the same efficacy as 2 g/kg IVIG and can be an option for the initial therapy of KD patients.

High-dose versus low-dose intravenous immunoglobulin for treatment of children with Kawasaki disease weighing 25 kg or more

Little is known whether 2-g/kg IVIG is necessary for older children with Kawasaki disease (KD), because they could have more complications and financial burden. The purpose of this study was to compare outcomes between high- and low-dose IVIG in KD children with higher body weight (25 kg or more), using a national inpatient database in Japan from 2010 to 2017. We identified those receiving 2-g/kg and 1-g/kg IVIG as an initial treatment. Outcomes included the proportions of coronary artery abnormality (CAA) formation, IVIG resistance, adverse effects, length of stay, and medical costs. A propensity score matching analysis was conducted to compare the outcomes between the groups. We identified 1332 patients with KD and created 4:1 propensity score-matched pairs between high- and low-dose IVIG groups. There were no significant differences in the proportions of CAA (5.3% vs. 4.1%; p = 0.587), IVIG resistance, and length of stay. Medical costs were significantly higher in the high-dose group than in the low-dose group (p < 0.001).Conclusion: No significant difference was shown between the high- and low-dose IVIG groups in the proportions of outcomes, while medical costs were higher in the high-dose group. Further studies are needed to ascertain the appropriate IVIG dose in older patients with KD. What is Known: • For treatments of Kawasaki disease at any age in the acute phase, 2-g/kg single-dose intravenous immunoglobulin and aspirin have been the most recommended to reduce fever early and prevent complications of coronary artery abnormalities. What is New: • There was no significant difference in outcomes between children with Kawasaki disease weighing ≥ 25 kg treated with high-dose or low-dose IVIG in terms of coronary artery abnormalities, IVIG resistance, adverse effects, and length of stay, except for medical costs.

Relationship between post-IVIG IgG levels and clinical outcomes in Kawasaki disease patients: new insight into the mechanism of action of IVIG

INTRODUCTION/OBJECTIVES

The dosing of intravenous immunoglobulin (IVIG) therapy for Kawasaki disease (KD) has been a matter of debate for decades, with recent studies implicating that larger doses lead to better outcomes. Despite this, few have investigated post-IVIG infusion immunoglobulin G (IgG) levels in relation to outcomes of KD such as response to IVIG and development of coronary artery abnormalities (CAAs). The present study investigated how varying levels of post-infusion IgG affected these outcomes.

METHOD

We collected demographic and laboratory data, including post-infusion IgG, from children with KD who were admitted to six hospitals in Japan between 2006 and 2012. We conducted multivariate analyses to examine the relationship between independent variables and non-response to IVIG and development of CAAs. We used random forest, a decision tree-based machine learning tool, to investigate the marginal effect of varying post-infusion IgG levels on non-response to IVIG and development of CAAs.

RESULTS

Of 456 patients included in the study, 130 (28.5%) were non-responders and 38 (8.3%) developed CAAs. Sodium, post-infusion IgG, and AST were significantly associated with non-response. Post-infusion IgG and sodium were significantly associated with CAA development. The random forest plots revealed a decrease in non-response and CAA rates with increasing post-infusion IgG until post-infusion IgG was near the median (2821 mg/dL), after which the non-response and CAA rates leveled off.

CONCLUSIONS

Greater post-infusion IgG is associated with better response to IVIG and decreased CAA development in KD patients, but this effect levels off at post-infusion IgG levels greater than the median. Key points • Though previous studies have shown that post-intravenous immunoglobulin (IVIG) infusion immunoglobulin G (IgG) is associated with non-response to IVIG therapy and coronary artery abnormality (CAA) development in Kawasaki disease (KD) patients, no study has investigated the relationship between varying levels of post-infusion IgG and these clinical outcomes. • Our study showed that non-response to IVIG therapy and CAA development in Kawasaki disease patients follow a decreasing trend with increasing post-infusion IgG at post-infusion IgG levels below the median. • At values of post-infusion IgG greater than the median, non-response and CAA development rates remain relatively constant with increasing post-infusion IgG. • Our study suggests that when post-infusion IgG is greater than the median, IgG may have fully bound to the therapeutic targets of KD, and in these patients, there may be limited benefit in administering additional IVIG.

Clinical Utility of Highly Purified 10% Liquid Intravenous Immunoglobulin in Kawasaki Disease

Compared with a 5% intravenous immunoglobulin, a 10% intravenous immunoglobulin as the first-line treatment of Kawasaki disease significantly reduced the fever duration (10 vs 13 hours, P = .022) among the responders, and the interval to adjunctive therapy for nonresponders (47 vs 49 hours, P = .035). There were no severe adverse events.

Adverse Effects of Immunoglobulin Therapy

Immunoglobulin has been widely used in a variety of diseases, including primary and secondary immunodeficiency diseases, neuromuscular diseases, and Kawasaki disease. Although a large number of clinical trials have demonstrated that immunoglobulin is effective and well tolerated, various adverse effects have been reported. The majority of these events, such as flushing, headache, malaise, fever, chills, fatigue and lethargy, are transient and mild. However, some rare side effects, including renal impairment, thrombosis, arrhythmia, aseptic meningitis, hemolytic anemia, and transfusion-related acute lung injury (TRALI), are serious. These adverse effects are associated with specific immunoglobulin preparations and individual differences. Performing an early assessment of risk factors, infusing at a slow rate, premedicating, and switching from intravenous immunoglobulin (IVIG) to subcutaneous immunoglobulin (SCIG) can minimize these adverse effects. Adverse effects are rarely disabling or fatal, treatment mainly involves supportive measures, and the majority of affected patients have a good prognosis.

Epidemiologic survey of Kawasaki disease in Inner Mongolia, China, between 2001 and 2013

The epidemiologic features of Kawasaki disease (KD) in the Inner Mongolia Autonomous Region of China has not been previously determined, to the best of our knowledge. Therefore, the aim of the present study was to investigate the epidemiology of KD in Inner Mongolia. Clinical data from 518 patients treated for KD in Inner Mongolia between January 2001 and December 2013 were analyzed. The results indicated that the mean annual incidence rate was 3.55±2.96 per 100,000 children under the age of 5 years between 2001 and 2013. The age at diagnosis ranged between 49 days and 14 years, while the disease occurred more frequently in the spring and summer. In addition, the incidence of coronary artery lesion (CAL) was reported to be 40.2% in the present survey. KD patients in the Han Chinese ethnic group were more likely to be complicated by CAL, whereas patients with incidence of KD in July were less likely to be complicated by CAL. In conclusion, the incidence of KD was observed to be increasing in Inner Mongolia, while the ethnic group and month of onset may be associated with the incidence of CAL in KD patients.

A review of current indications, adverse effects, and administration recommendations for intravenous immunoglobulin

OBJECTIVE

To review and summarize the body of literature regarding human intravenous immunoglobulin (hIVIG) therapy in veterinary medicine. Mechanism of action, usage in human medicine, adverse effects of therapy, implications for veterinary use, and administration recommendations are discussed.

DATA SOURCES

Current human and veterinary peer-reviewed medical literature including original research articles and scientific reviews.

HUMAN DATA SYNTHESIS

There are currently 6 labeled uses for hIVIG in human medicine, but preparations are used off-label to successfully treat multiple immune-mediated conditions. To maximize the potential of hIVIG use in animals and identify areas deficient in research, a review of the current literature is warranted.

VETERINARY DATA SYNTHESIS

Investigation of hIVIG therapy in veterinary patients has been limited to the subjects of immune-mediated hemolytic anemia (IMHA), immune-mediated thrombocytopenia (ITP), Evan's syndrome, cutaneous disease, myasthenia gravis (MG), and sudden acquired retinal degeneration (SARDS). Proponents of veterinary hIVIG use believe administration may reduce transfusion requirements and decrease hospitalization time.

CONCLUSION

Immunoglobulin (Ig) has not been shown to decrease transfusion requirements in IMHA patients, but shows great promise for treatment of ITP and dermatological diseases. Although serial transfusion of hIVIG is employed in human medicine, repeated transfusion is not recommended in animals due to risk of severe allergic reaction. Other potential adverse effects of transfusion include delayed hypersensitivity reactions, thromboembolism, renal failure, hypotension, and aseptic meningitis.

Association of lower eosinophil-related T helper 2 (Th2) cytokines with coronary artery lesions in Kawasaki disease

Kawasaki disease (KD) is a systemic febrile vasculitis particular coronary artery involvement. Eosinophilia has been found in our and other studies in KD. This study further investigates whether eosinophil-related T helper 2 (Th2) cytokines or the activation marker (eosinophil cationic protein - ECP) is involved in KD with coronary artery lesions (CAL). A total of 95 KD patients were enrolled for this study. Plasma samples were subjected to the measurement of interleukin (IL)-4, IL-5, and eotaxin by Luminex-Bedalyte multiplex beadmates system and to the measurement of ECP by fluoroimmunoassay. Patients with KD had higher eosinophils than controls. Eosinophil-related mediators: IL-4, IL-5, eotaxin, and ECP levels were also higher in KD patients than controls before intravenous immunoglobulin (IVIG) treatment. After IVIG treatment, ECP decreased but IL-4, IL-5, and eotaxin increased significantly. The higher the IL-5 and eosinophil levels after IVIG treatment, the lower rate of CAL was found. Changes of eosinophils after IVIG treatment were positively correlated to changes of IL-5 levels but not ECP levels. An increase of eosinophils and IL-5, but not ECP levels after IVIG treatment, was inversely correlated with CAL formation in KD.

Impact of intravenous immunoglobulin infusion on longitudinal left ventricular performance in patients with acute Kawasaki disease of usual course

PURPOSE

To determine the acute change in cardiac performance after intravenous immunoglobulin infusion (IVIG) in patients with acute Kawasaki disease (KD).

MATERIALS AND METHODS

Subjects were 33 patients with KD who were treated with IVIG 2 g/kg and recovered without coronary artery lesion and 27 controls. Subjects underwent combined two-dimensional, Doppler, and tissue Doppler echocardiographic (TDI) studies. In KD, these echocardiographic studies were performed before IVIG, 48 h after IVIG, and in convalescence. Echocardiographic variables were compared between KD and controls as well as among 3 time points in KD.

RESULTS

Before IVIG, KD showed significantly higher peak aortic velocity and shorter aortic ejection time as results of tachycardia and significantly lower E' (p<0.04) but significantly higher E/E' (p<0.02). After IVIG, patients with KD became afebrile and showed significantly lower TDI indices such as S', E', and, A' and isovolumic acceleration (IVA) (163+/-56 vs. 208+/-70 cm/s(2), p<0.01) with higher TDI-derived Tei index (0.50+/-0.10 vs. 0.44+/-0.06, p<0.02) than controls. These differences tended to disappear in convalescence. In analysis of repeated measurements, except for hemodynamic changes associated with tachycardia, S' (7.9+/-1.3 vs. 7.0+/-1.1 vs. 7.4+/-0.9 cm/s, p<0.001), IVA (227+/-72 vs. 163+/-56 vs. 180+/-63, p<0.05), and A' (7.7+/-3.0 vs. 5.6+/-1.3 vs. 6.7+/-2.3 cm/s, p<0.001) were significantly different among these time points.

CONCLUSIONS

In patients with acute KD with usual course, IVIG induced transient sub-clinical longitudinal left ventricular dysfunction.

Analysis of thromboembolic risk related to high-dose intravenous immunoglobulin treatment: a preliminary clinical study of 10 patients with autoimmune mucocutaneous blistering diseases

BACKGROUND

Intravenous immunoglobulin (IVIg) treatment is a well-known treatment that has been used successfully in a broad spectrum of autoimmune diseases. Currently no data are available in the literature about the role of IVIg in the pathogenesis of thromboembolic events in patients with autoimmune blistering diseases refractory to conventional immunosuppressive treatment.

AIM

To determine the relationship between IVIg and thromboembolism in patients with autoimmune blistering diseases and to establish a protocol to deal with the thromboembolic risk.

METHODS

In our preliminary clinical study, 10 patients with autoimmune blistering diseases underwent IVIg cycles to a total of 133 cycles in all (total number of infusions in the patient group: 399), at a standard dose of 2 g/kg/infusion accompanied by an accurate and a complete clinical and laboratory screening for thromboembolism. Preventive measures, such as hydration before and after IVIg, and administration of 100 mg of acetyl salicylic acid (aspirin) or 1000 IU of subcutaneous heparin calcium per day for 3 weeks, were introduced to reduce the thromboembolic risk.

RESULTS

Throughout the 2 years of IVIg treatment, no patient developed a superficial and/or deep venous or arterial thrombosis, even though some of the patients had underlying thromboembolic risk factors and had tested positive for some congenital and acquired thrombophilia markers.

CONCLUSIONS

Our results indicate that thromboembolic events are uncommon, despite the presence of risk factors. However, as these disorders are very rare and the percentage of nonresponder patients is very low, further investigations are needed to better understand whether IVIg alone is able to trigger these fatal events in blistering disorders.

Effect of revision of Japanese diagnostic criterion for fever in Kawasaki disease on treatment and cardiovascular outcome

BACKGROUND

The aim of this study was to investigate the effect of a revision of the fever criterion for initial intravenous immunoglobulin (IVIG) treatment, and cardiovascular sequelae, in the new Japanese diagnostic criteria for Kawasaki disease.

METHODS AND RESULTS

Patients who were reported in the 16th and 18th nationwide surveys in Japan were analyzed. New criteria group comprised patients who received the diagnosis of Kawasaki disease in the 18th nationwide survey (n=18,789). Old criteria group was comprised patients who received their diagnosis in the 16(th) nationwide survey (n=15,017). The difference between the new and old criteria for complete cases was only 1%. The proportion of patients who were treated with IVIG within 4 days of illness onset in the new criteria group was significantly lower than in the old criteria group (27.7% vs 30.7%). Multivariate logistic regression analysis identified criteria sex, age, recurrence, diagnosis, last day of initial IVIG and additional IVIG treatment as significant independent factors for cardiovascular sequelae.

CONCLUSIONS

The guideline revision improves diagnostic sensitivity somewhat, but reflects the clinical reality of the disease that approximately 30% of patients are treated with IVIG within 4 days of illness onset.

Impairment of angiogenic activity in the serum from patients with coronary aneurysms due to Kawasaki disease

BACKGROUND

The inflammatory mediators play an important role in the progression of coronary vasculitis in Kawasaki disease (KD), but effects of KD serum including inflammatory mediators on endothelial cells remain unknown. We hypothesized that serum activity to stimulate in vitro human umbilical vein endothelial cells (HUVEC) tube formation might be impaired in KD.

METHODS AND RESULTS

Serum from patients with coronary aneurysms was less active in stimulating HUVEC tube formation than serum from patients without coronary aneurysms or febrile controls. In patients with coronary aneurysms, the reduction in the serum angiogenic activity was documented already before KD treatment (p=0.03 vs healthy controls, p=0.08 vs febrile controls) and enhanced after intravenous immune globulin plus aspirin (p<0.001 vs healthy controls, p=0.002 vs febrile controls); both drugs did not affect the assay studied. This reduction was greater in patients who later developed giant aneurysms >8 mm compared with those who developed small to moderate aneurysms (p=0.01). The reduced serum angiogenic activity was partly caused by the reduction in the serum activity of stimulating HUVEC proliferation.

CONCLUSIONS

Serum activity to stimulate HUVEC tube formation was impaired in KD patients who later developed larger coronary aneurysms, which may be associated with the severity of vascular injury.

Abnormal Tissue Doppler Images are Associated With Elevated Plasma Brain Natriuretic Peptide and Increased Oxidative Stress in Acute Kawasaki Disease

BACKGROUND

The aims of this study were to evaluate myocardial mechanics using pulsed tissue Doppler imaging (TDI), and to determine the relationship between abnormal myocardial performance and plasma brain natriuretic peptide (BNP) levels and oxidative stress in acute Kawasaki disease (KD).

METHODS AND RESULTS

Consecutive TDI parameters, including peak systolic velocity (Sw) and early (Ew) and late diastolic excursion of the mitral annuli were obtained in 42 patients with KD (mean age: 2.4+/-0.4 years) in weeks 1, 2, and 3, and during convalescence. Plasma BNP level and urinary 8-isoprostane were also examined during the acute phase. These data were then compared with TDI profiles from 62 healthy children, plasma BNP levels in 38 controls with other febrile illnesses, and urinary 8-isoprostane levels in 13 healthy children. Ew in week 1 was significantly lower than in controls, subsequently normalizing in the convalescent stage. Plasma BNP level in acute KD patients was significantly higher (65+/-9 pg/ml) than in controls (13+/-2 pg/ml). Urinary 8-isoprostane level in acute KD patients was significantly higher as compared with control (596 +/-37 vs 379+/-26 pg/ml Cr, p<0.05). There was a significant negative correlation between week 1 Sw and plasma BNP level (r=-0.55, p=0.0001). Change in Sw velocity in the BNP >/=51 group was significantly greater than in the BNP <51 group. There was a significant negative correlation between week 1 Sw and urinary 8-isoprostane level (r=-0.48, p=0.001).

CONCLUSIONS

Latent abnormal tissue Doppler profiles, possibly reflecting long-axis systolic and diastolic dysfunction have been noted in KD patients. Abnormal myocardial mechanics may contribute to the increased plasma BNP level and enhanced oxidative stress may contribute to cardiac dysfunction in KD.

Intravenous immunoglobulin-associated arterial and venous thrombosis; report of a series and review of the literature

BACKGROUND

To date, the prevalence of intravenous immunoglobulin (IvIg)-related thrombotic complications has not been evaluated in patients with autoimmune disorders followed up in Departments of Internal Medicine.

OBJECTIVES

To assess prevalence and characteristics of IvIg-related thrombotic complications in patients with autoimmune disorders receiving IvIg therapy; to evaluate the predictive factors for onset of IvIg-related thrombotic manifestation in patients, and to detect patients at risk for these types of complications.

PATIENTS AND METHODS

The medical records of 46 patients with autoimmune disorders who were given IvIg therapy at our Department of Internal Medicine between January 2002 and December 2004 were reviewed.

RESULTS

Among the 46 patients, nine exhibited IvIg-associated severe complications (19.6%). Six patients (13%) developed IvIg-related thrombotic complications. Thrombotic complications frequently occurred during IvIg infusion (50%), although they were also observed within 1-8 days following IvIg infusion in other patients. IvIg-related thrombotic complications consisted of: deep venous thrombosis or pulmonary embolism (n = 3), myocardial infarction (n = 2) and stroke (n = 1). The outcome of thrombotic complications was favourable in all patients, after appropriate therapy institution. Older age, history of associated arterial hypertension and hypercholesterolaemia were more common in the group of patients with IvIg-related thrombotic complications.

CONCLUSIONS

Our study demonstrates that IvIg-related thrombotic arterial/venous complications are not uncommon in patients with autoimmune disorders (13% of patients). Nevertheless, patients, who are followed up in Departments of Internal Medicine often have concomitant disorders placing them at increased risk to develop IvIg-related thrombotic complications; the latter may also explain the high rate of IvIg-related thrombosis in our cohort. Our series further indicates that patients should be monitored closely for these types of adverse events during the whole period of IvIg therapy, as thrombotic manifestations occurred in patients who had received multiple IvIg infusions without exhibiting complications. In addition, our results suggest that it is questionable to initiate IvIg therapy in patients presenting with predictive factors of thrombotic complications; in this subgroup of patients, IvIg should be prescribed cautiously, after re-weighing risk-benefit considerations.

Four cases of Kawasaki syndrome complicated with myocarditis

BACKGROUND

Myocarditis frequently occurs in the acute phase of Kawasaki syndrome (KS), and a few severe cases have been reported. Four cases of myocarditis in KS required additional catecholamine treatment because of severe left ventricular dysfunction (LVD).

CASE REPORTS

Three cases were relatively older children and 2 cases were complicated with encephalopathy. All 4 developed coronary artery abnormalities during convalescence. There was 1 case of LVD because of prolonged severe inflammation prior to administration of intravenous immunoglobulin (IVIG). The remaining 3 patients had normal values for ejection fraction before the administration of IVIG but decreased values (42-51%) and increased C-reactive protein levels after IVIG administration. These cases demonstrate an association between myocarditis in KS and severe or worsened inflammation.

CONCLUSIONS

Even with prior normal echocardiography, careful observation of cardiac function may be necessary for patients with KS, especially older children, when inflammation deteriorates after administration of IVIG.