Objective: To report severe hemolytic adverse reactions caused by intravenous infusion of human immunoglobulin (IVIG) in a child, and to alert clinical staff to be aware of IVIG-associated hemolytic reactions to ensure transfusion safety in pediatric populations. Methods: A retrospective analysis was conducted on a case of severe hemolytic reaction following high-dose IVIG infusion in a pediatric patient with severe pneumonia. Results: Following high-dose IVIG infusion, severe hemolytic adverse reactions developed, clinically manifesting as decreased hemoglobin, progressively elevated bilirubin and lactate dehydrogenase (LDH), and gradual hepatomegaly. IgG antibodies were detected in the patient's erythrocytes and plasma. Conclusion: When patients passively acquire IgG antibodies through IVIG infusion, timely monitoring of antibody titers in vivo is critical. For subsequent transfusions, red blood cell products that lack the corresponding antigens should be selected to mitigate hemolysis. Clinicians should remain vigilant against rare but severe hemolytic adverse reactions.

BACKGROUND:Growth factor is the key effect molecule that plays a role in platelet-rich plasma in clinical treatment.There are differences in the concentration of growth factor after different activators activate platelet-rich plasma,which is an important factor affecting clinical efficacy. OBJECTIVE:To analyze the influence of different activators on the mass concentration of growth factors in platelet-rich plasma. METHODS:Totally 12 healthy volunteers were recruited to collect EDTA-K2 anticoagulant venous blood.Secondary centrifugation was used to prepare platelet-rich plasma.The difference in mass concentrations of growth factors was compared between venous blood and platelet-rich plasma.The platelet-rich plasma was mixed with four activators(normal saline,thrombin,calcium gluconate,calcium gluconate+thrombin)according to the volume ratio of 10:1,and incubated in a constant temperature water bath at 37 °C for 30 minutes.After centrifugation,the supernatant was extracted and the mass concentration of growth factor was detected.The bacterial growth in supernatant was measured by blood agar plate.Pearson correlation was used to analyze the correlation between different activators and the mass concentration of growth factor in platelet-rich plasma,and the correlation between the value of thrombocytometer and the mass concentration of growth factors in platelet-rich plasma. RESULTS AND CONCLUSION:(1)The mass concentrations of platelet-derived growth factor-BB,platelet-derived growth factor-AB,vascular endothelial growth factor,and epidermal growth factor in platelet-rich plasma were 8.7,22.2,2.3,and 2.8 times of those in venous blood,respectively(P<0.05).(2)Compared with normal saline group,the mass concentrations of platelet-derived growth factor BB,platelet-derived growth factor AB,vascular endothelial growth factor,and epidermal growth factor were increased in the thrombin group,calcium gluconate group,and calcium gluconate+thrombin group(P<0.05).The mass concentration of platelet-derived growth factor BB in the thrombin group and calcium gluconate group was higher than that in the calcium gluconate+thrombin group(P<0.05),and the mass concentration of platelet-derived growth factor AB in the thrombin group was higher than that in the calcium gluconate group and calcium gluconate+thrombin group(P<0.05).Epidermal growth factor mass concentration in the thrombin group was lower than that in the calcium gluconate group and calcium gluconate+thrombin group(P<0.05).(3)The results of blood agar plate test showed no bacterial growth in the supernatant of the four groups.(4)Pearson correlation analysis showed that the mass concentration of platelet-derived growth factor BB in platelet-rich plasma was strongly positively correlated with thrombin(r=0.683,P<0.05),and the mass concentration of vascular endothelial growth factor was strongly positively correlated with thrombin,calcium gluconate,calcium gluconate+thrombin stimulant(r=0.730,0.789,0.686,P<0.05).There was no correlation between the value of thrombocytometer and the mass concentration of four kinds of growth factors(P>0.05).(5)The results suggest that different activators have an impact on the concentration of growth factors in platelet-rich plasma.It is suggested to choose different activators to improve clinical efficacy according to different growth factor mass concentrations and treatment needs.

[Objective] To compare the characteristics of platelet-rich plasma derived exosomes (PRP-Exos) under different activation conditions and their differential effects on the proliferation capacit of human microvascular endothelial cells (HMEC-1) and human skin fibroblasts (BJ). [Methods] Ten healthy volunteers were recruited, and 10 mL of venous blood anticoagulated with EDTA-K2 was collected. PRP-Exos were prepared and extracted by the secondary centrifugation method. Transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blotting (WB) detection techniques were used to compare the morphological characteristics, particle size distribution, concentration, and the expression of surface marker proteins of PRP-Exos. Through in vitro cell culture, the differences in morphological changes and proliferation abilities of HMEC-1 and BJ cells induced by PRP-Exos in different activator groups were compared. [Results] 1) TEM observation showed that the morphologies of PRP-Exos in different activator groups were different. 2) NTA analysis showed that compared with the particle size of (109.60±2.71) nm in the normal saline group, the particle sizes of the thrombin group [(104.93±1.55) nm] and the mixed agent group [(103.83±1.58) nm] were relatively smaller, while the particle size of the calcium gluconate group [(113.57±4.70) nm] was larger and its particle size distribution range was wider. There were statistically significant differences among different groups (F=7.019, P<0.05). The concentration of exosomes obtained in the group with the mixture of calcium gluconate and thrombin was the highest [(4.87±0.63)×10⁶ particles/mL, P<0.001]. Both the thrombin group [(2.75±0.13)×10⁶ particles/mL, P < 0.01] and the calcium gluconate group [(3.82±0.06)×10⁶ particles/mL, P<0.001] obtained higher concentrations of exosomes compared with the normal saline group. The concentration in the calcium gluconate group was slightly higher than that in the thrombin group, and there was a significant difference between the two groups (P<0.05). 3) WB analysis showed that CD41, CD81, and TSG101 were expressed on the surface of PRP-Exos, and the protein signal intensities of CD41 and TSG101 in the group with the mixture of thrombin and calcium gluconate were the strongest (P<0.001). 4) The results of in vitro cell culture showed that PRP-Exos in the group with the mixture of thrombin and calcium gluconate could significantly promote the proliferation of HMEC-1 and BJ cells (P<0.05). [Conclusion] The PRP treated with the thrombin and calcium gluconate mixture group yielded the highest concentration of exosomes; under in vitro culture conditions, PRP-Exos from this group significantly promoted the proliferation of HMEC-1 and BJ cells.

Objective:To investigate the completion rate of tumor evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients in the national multicenter real-world database.Methods:The prospective real-world study was conducted. The clinicopathological data of 1 074 patients who underwent surgical treatment for mid and low rectal cancer in 47 national medical institutions, including Peking Union Medical College Hospital et al, from May 12,2023 to May 11,2024 were collected. Observation indicators: (1) clinical characteristics of patients with mid and low rectal cancer; (2) initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer; (3) initial imaging evaluation of patients with mid and low rectal cancer; (4) imaging evaluation after neoadjuvant therapy for patients with mid and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M( Q1, Q3). Count data were described as absoluter numbers and/or percentages. Results:(1) Clinical characteristics of patients with mid and low rectal cancer. Of the 1 074 patients, there were 713 males and 361 females, aged 63(56,70)years. The body mass index of 1 074 patients was 24(21,26)kg/m 2.For American Society of Anesthesiologists classification, there were 147 cases of stage Ⅰ, 641 cases of stage Ⅱ, 157 cases of stage Ⅲ, 2 cases of stage Ⅳ, and there were 127 cases missing data. (2) Initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer. Of the 1 074 patients, there were 787 cases (73.28%) undergoing complete colonoscopy, and there were only 197 cases (18.34%) undergoing immunohistochemical evaluation of all four mismatch repair proteins. (3) Initial imaging evaluation of patients with mid and low rectal cancer. Of the 1 074 patients, there were 842(78.40%) patients completing magnetic resonance imaging (MRI) or ultrasound evaluation, and there were 914(85.10%) patients completing chest, abdomen, and pelvis enhanced computed tomography (CT) evaluation. In the 149 patients completing rectal ultrasound evaluation, there were 122 cases (81.88%) comple-ting T staging evaluation, and there were 81 cases (54.36%) completing N staging evaluation. In the 808 patients completing rectal MRI evaluation, there were 708 cases (87.62%) completing T staging evaluation, and there were 590 cases (73.02%) completing N staging evaluation. (4) Imaging evalua-tion after neoadjuvant therapy for patients with mid and low rectal cancer. Of the 388 patients with neoadjuvant therapy, there were 332 patients (85.57%) completing MRI or ultrasound evaluation, and there were 327 patients (84.28%) completing chest, abdomen, and pelvis enhanced CT evalua-tion. In the 70 patients completing rectal ultrasound evaluation, there were 65 cases (92.86%) com-pleting T staging evaluation, and there were 49 cases (70.00%) completing N staging evaluation. In the 327 patients completing rectal MRI evaluation, there were 246 cases (75.23%) completing T staging, and there were 228 cases (69.72%) completing N staging evaluation. Conclusion:The com-pletion rate of tumor imaging evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients on a national scale is relatively good.

Objective:To investigate the completion rate of tumor evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients in the national multicenter real-world database.Methods:The prospective real-world study was conducted. The clinicopathological data of 1 074 patients who underwent surgical treatment for mid and low rectal cancer in 47 national medical institutions, including Peking Union Medical College Hospital et al, from May 12,2023 to May 11,2024 were collected. Observation indicators: (1) clinical characteristics of patients with mid and low rectal cancer; (2) initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer; (3) initial imaging evaluation of patients with mid and low rectal cancer; (4) imaging evaluation after neoadjuvant therapy for patients with mid and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M( Q1, Q3). Count data were described as absoluter numbers and/or percentages. Results:(1) Clinical characteristics of patients with mid and low rectal cancer. Of the 1 074 patients, there were 713 males and 361 females, aged 63(56,70)years. The body mass index of 1 074 patients was 24(21,26)kg/m 2.For American Society of Anesthesiologists classification, there were 147 cases of stage Ⅰ, 641 cases of stage Ⅱ, 157 cases of stage Ⅲ, 2 cases of stage Ⅳ, and there were 127 cases missing data. (2) Initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer. Of the 1 074 patients, there were 787 cases (73.28%) undergoing complete colonoscopy, and there were only 197 cases (18.34%) undergoing immunohistochemical evaluation of all four mismatch repair proteins. (3) Initial imaging evaluation of patients with mid and low rectal cancer. Of the 1 074 patients, there were 842(78.40%) patients completing magnetic resonance imaging (MRI) or ultrasound evaluation, and there were 914(85.10%) patients completing chest, abdomen, and pelvis enhanced computed tomography (CT) evaluation. In the 149 patients completing rectal ultrasound evaluation, there were 122 cases (81.88%) comple-ting T staging evaluation, and there were 81 cases (54.36%) completing N staging evaluation. In the 808 patients completing rectal MRI evaluation, there were 708 cases (87.62%) completing T staging evaluation, and there were 590 cases (73.02%) completing N staging evaluation. (4) Imaging evalua-tion after neoadjuvant therapy for patients with mid and low rectal cancer. Of the 388 patients with neoadjuvant therapy, there were 332 patients (85.57%) completing MRI or ultrasound evaluation, and there were 327 patients (84.28%) completing chest, abdomen, and pelvis enhanced CT evalua-tion. In the 70 patients completing rectal ultrasound evaluation, there were 65 cases (92.86%) com-pleting T staging evaluation, and there were 49 cases (70.00%) completing N staging evaluation. In the 327 patients completing rectal MRI evaluation, there were 246 cases (75.23%) completing T staging, and there were 228 cases (69.72%) completing N staging evaluation. Conclusion:The com-pletion rate of tumor imaging evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients on a national scale is relatively good.

Objective To study the changes in serum immunoglobulin levels in children with thalassemia who undergo repeated blood transfusions and explore their correlation with delayed hemolytic transfusion reactions(DHTR).Methods Serum samples from children with thalassemia who received blood transfusion treatment from June 2022 to April 2023(ob-servation group)and healthy children who underwent physical examination(control group)in our hospital were collected.The levels of serum immunoglobulins(IgG subtype,IgM,IgA,IgE and IgD)were detected using flow cytometry CBA multi-factor quantitative detection technology,and the differences between the two groups were compared.The children were divided into 4 groups according to different transfusion numbers:≤10 numbers,11-30 numbers,31-50 numbers and＞50 numbers,and the differences between different blood transfusion numbers and serum immunoglobulin levels in each group were compared using one-way analysis of variance(ANOVA).Children with thalassemia with DHTR were in the hemolysis group,and children with thalassemia who did not experience DHTR were in the non-hemolysis group.The changes in serum immunoglobulins(IgG subtypes,IgM,IgA,IgE and IgD)between the two groups were compared to explore the correlation between serum immunoglobulins in thalassemia children with repeated transfusion and DHTR.Results The levels of IgG1,IgG3,IgG4 and IgA in the observation group were significantly higher than those in the control group,with the increase of(2.07±2.12),(0.67±2.03),(0.30±0.37)and(6.04±11.40)mg/mL,respectively,while the level of IgD in observation group was significantly lower than that in the control group,with a decrease of(0.03±0.01)mg/mL,P＜0.05.No significant difference was noticed in IgG2,IgM and IgE between the groups(P＞0.05).IgG1 and IgG4 both significantly increased with the number of blood transfusions.The IgG1 in the 4 groups increased sequentially as(0.30±0.62),(0.41±0.51)and(3.60±3.48)mg/mL,and IgG4 increased sequentially as(0.12±0.13),(0.22±0.07)and(0.21±0.38)mg/mL.IgG2,IgM and IgD showed a significant decrease,with IgG 2,IgM,and IgD in four groups decreased as(0.91±1.50),(0.14±0.10)and(0.05±0.05)mg/mL,respectively,showing significant differences with the number of blood transfusions(P＜0.05).No sig-nificant difference was found in IgG3,IgA and IgE with different number of transfusions(P＞0.05).IgG1,IgG3 and IgG4 in the hemolysis group were significantly higher than those in the non-hemolysis group,with an increase of(4.44±3.41),(0.73±1.26)and(0.52±0.40),respectively(P＜0.05).IgD in the hemolysis group was significantly lower than that in the non-hemolysis group,with a decrease of(0.00±0.06)mg/mL,P＜0.05.No significance was noticed in IgG2,IgM,IgA and IgE between the hemolysis group and the non-hemolysis group(P＞0.05).Conclusion The serum immunoglobulin levels of children with thalassemia who undergo repeated blood transfusions are abnormal.There are differences in correlation between the number of blood transfusions and serum immunoglobulin levels among children with thalassemia who undergo repeated blood transfusions.The relevant serum immunoglobulins for DHTR in children with thalassemia who undergo repeated blood transfusions are IgG1,IgG3 and IgG4.

【Objective】 To investigate the changes in cellular immunity (peripheral blood lymphocyte subsets) and humoral immunity (serum immunoglobulin and ferritin) status among children with thalassemia who received repeated transfusions in Yunnan. 【Methods】 Forty-six children with thalassemia who underwent repeated blood transfusions from January 2020 to October 2022 were selected as the observation group. Forty children with thalassemia who did not receive blood transfusion were included in control group 1, and 46 healthy children underwent physical examination were included in control group 2. The differences in lymphocyte subsets, serum immunoglobulin levels and ferritin concentrations were compared among the three groups. 【Results】 For lymphocyte subsets: CD3⁺, CD4⁺ and CD4⁺/CD8⁺ in the observation group was lower than the control group 1 and 2: 57.60±8.36 vs 64.57±7.56 vs 66.58±5.65, 33.16±5.67 vs 38.62±8.36 vs 38.62±6.41 and 1.49±0.09 vs 2.32±0.15 vs 2.13±0.16, respectively; CD16⁺ CD56⁺ in the observation group was lower than the control group 2: 11.21±5.06 vs 16.70±7.92; CD8⁺ in the observation group was higher than control group 1 and control group 2: 26.63± 1.75 vs 20.60±1.43 vs 18.92±0.84; CD19⁺ in the observation group was higher than the control group 2: 24.06±6.42 vs 19.67 ±8.42, P<0.05, but no significant difference was noticed between the two control groups(P>0.05). For serum immunoglobulin and ferritin: IgG and ferritin in the observation group were higher than control group 1 and control group 2: 10.59±3.88 vs 7.02±3.88 vs 5.58±1.98 and 2 037.37±1 377.59 vs 72.63±56.71 vs 59.48±33.88. IgA in the observation group was higher than the control group 2: 1.06±0.92 vs 0.39±0.32(P<0.05), but no significant difference was noticed between the two control groups (P>0.05). The difference of IgM and IgE between the three groups was not significant (P > 0. 05). 【Conclusion】 The proportion of lymphocyte subsets in thalassemia children with repeated blood transfusion was imbalanced,and the level of immunoglobulin in humoral immunity was abnormal.

【Objective】 To share the experience of autologous platelet-rich plasma(PRP) combined therapy in successful treatment of refractory osteomyelitis with fractures in children. 【Methods】 One case of refractory osteomyelitis with fracture in children failed to respond to traditional treatment for more than 14 months. A total of 20 mL of whole blood was collected from the child, and 6 mL of PRP with 4 to 5 times concentration was prepared by secondary centrifugation. To prepare 2 cm×2 cm platelet concentrate gel (PG), 3 mL of PRP was mixed with a 0.3 mL activator which was then covered with an absorbable dressing. A three-way tube sprayed the remaining 3 mL of PRP and 0.3 mL activator into the surrounding tissues. 【Results】 The X-ray film of the patient followed up for 1 week showed that the fracture line was blurred, and the fracture end had obvious callus formation. The X-ray film reexamination at 4 months showed that the fracture end healed well, the fracture surface healed, and the osteomyelitis healed. 【Conclusion】 Autologous PRP has a good effect in the treatment of refractory osteomyelitis combined with fracture in children, which can provide a new method for clinical treatment.

【Objective】 To study the yielding rate and distribution of unexpected antibodies in blood transfusion children with thalassemia in Yunnan province, and to explore the blood transfusion strategies. 【Methods】 From January 2016 to December 2021, 298 children with thalassemia, who received blood transfusion treatment in Kunming, Xishuangbanna, Wenshan, Dehong, Yuxi and Baoshan hospitals across Yunnan Province, were selected. The unexpected antibodies of blood plasma were screened by microcolumn gel card. The samples with positive antibodies were identified for alloantibody specificity. 【Results】 Unexpected antibodies were yielded in 67 out of 298(22.48%) transfused children with thalassemia. The positive rates of unexpected antibodies in boys and girls were 16.55%(24/145) and 28.10%(43/153), respectively. The positive rates of unexpected antibodies in Han, Dai, Zhuang, Yi, Bulang, Jinuo and Miao people were 14.06%(18/128), 30.80%(32/104), 35.71%(10/28), 36.36%(8/22), 50.00%(4/8), 60.00%(3/5)and 66.67%(2/3), respectively, with statistically significant differences between each other. The positive rate of unexpected antibodies in ethnic minorities was higher than that in Han. The positive rates of unexpected antibodies in children who received the first transfusion at birth-one year old, 1~3 years old, 3~6 years old and above 6 years old were 12.50%(3/24), 10.14%(7/69), 24.54%(40/163)and 40.48%(17/42), respectively. The positive rates of unexpected antibodies in children with first transfusion after 3 years old were significantly higher than those before 3 years old. The positive rates of unexpected antibodies in children with one transfusion, 1~3, 3~10, 10~20 and more than 20 transfusions were 4.76%(1/21), 12.07%(7/58), 23.71%(23/97), 28.16%(29/103)and 36.84%(7/19), respectively, with statistically significant differences between each other. The number of blood transfusions was positively correlated with the unexpected antibody yielding. The yielding rate of unexpected antibodies in children with α thalassemia, βthalassemia, δ+ βthalassemia and untyped thalassemia was 7.50%(3/40), 17.62%(34/193), 53.70%(29/54)and 9.09%(1/11), respectively(P<0.05). The yielding rate of unexpected antibodies in transfused children with δ+ βthalassemia was the highest. And 57 unexpected antibodies of Rh blood group system were yielded, 6 anti-M antibodies, 2 anti-N antibodies and 2 undetermined. 【Conclusion】 The positive rate of unexpected antibodies in transfused children with thalassemia in Yunnan province is high. Routine antibody screening should be carried out for transfusion children with thalassemia, and blood units, compatible with ABO, Rh and MNS typing results, should be selected to ensure the safety and effectiveness of clinical blood use.

【Objective】 To analyze the effect of intravenous immunoglobulin(IVIG)-produced IgG antibody on the crossmatch incompatibility of neonates. 【Methods】 Blood type grouping, antibody screening, crossmatch, direct anti-globulin test, elution test, indirect antiglobulin test, and IVIG titer determination were conducted by microcolumn gel method. 【Results】 IgG anti-A were detected out in the elution test and free antibody test of 6 infants, and the titer of IgG anti-A contained in IVIG was 256, which led to the crossmatch incompatibility between infants and donors with the same type. 【Conclusion】 The hemolysis and crossmatch incompatibility in newborns, born to ABO-compatible mothers, may occur due to the IVIG-induced IgG antibodies. The O-type washed red blood cells should be selected for transfusion.