A 10-year-old girl was admitted with a 38-hour history of widespread subcutaneous petechiae and hematuria and a 6-hour history of jaundice and oliguria. Physical examination revealed widespread subcutaneous petechiae and jaundice of the skin and sclera. Laboratory tests showed anemia, thrombocytopenia, acute kidney injury, and markedly elevated lactate dehydrogenase. Thrombotic microangiopathy was initially diagnosed, with a high suspicion of atypical hemolytic uremic syndrome (aHUS). Eculizumab was initiated within 9 hours of admission (within 48 hours of onset). After the first infusion, hemolysis rapidly ceased, and the platelet count and renal function gradually returned to normal. Whole-exome sequencing identified homozygous deletions of CFHR1 exon 2 and CFHR4 exon 1. aHUS typically has abrupt onset and rapid progression. Clinicians should maintain high suspicion for aHUS when the triad of thrombocytopenia, microangiopathic hemolytic anemia, and acute kidney injury is present. Ultra-early eculizumab (within 48 hours of onset) rapidly blocks complement-mediated thrombotic microangiopathy, reverses organ injury, and improves long-term prognosis. Additionally, complement-related genetic testing is important for etiological clarification and individualized determination of eculizumab treatment duration.
Humans ; Antibodies, Monoclonal, Humanized/administration & dosage* ; Female ; Atypical Hemolytic Uremic Syndrome/drug therapy* ; Child ; Complement C3b Inactivator Proteins

Critical care emphasizes critical thinking, focuses on the triggers that lead to disease progression, and attaches great importance to early diagnosis of diseases and assessment of the compensatory capacity of vital organs. Pregnancy-associated atypical hemolytic uremic syndrome (P-aHUS) is relatively rare in the intensive care unit (ICU). Most cases occur within 10 weeks after delivery. Severe cases can be life-threatening. It characterized by microangiopathic hemolytic anemia, decreased platelet count (PLT), and acute kidney injury (AKI). Early clinical diagnosis is difficult due to its similarity to various disease manifestations. On January 28, 2024, a 26-year-old pregnant woman at 26⁺³ weeks gestation was transferred to the ICU 19 hours post-vaginal delivery due to abdominal pain, reduced urine output, decreased PLT, elevated D-dimer, tachycardia, increased respiratory rate and declined oxygenation. On the day of ICU admission, the critical care physician identified the causes that triggered the acute respiratory and circulatory events based on the "holistic and local" critical care thinking. The condition was stabilized rapidly by improving the capacity overload. In terms of etiological diagnosis, under the guidance of the "point and face" critical care thinking, starting from abnormality indicators including a decrease in hemoglobin (Hb) and PLT and elevated D-dimer and fibrin degradation product (FDP) without other abnormal coagulation indicators, the critical care physician ultimately determined the diagnosis direction of thrombotic microangiopathy (TMA) by delving deeply into the essence of the disease and formulating a laboratory examination plan in a reasonable and orderly manner. In terms of in-depth diagnosis, combining the disease development process, family history, and past history, applying the two-way falsification thinking of "forward and reverse" as well as "questioning and hypothesis", the diagnosis possibilities of preeclampsia, HELLP syndrome [including hemolysis (H), elevated liver function (EL) and low platelet count (LP)], thrombotic thrombocytopenic purpura (TTP), typical hemolytic uremic syndrome (HUS), and autoimmune inflammatory diseases inducing the condition was ruled out. The diagnosis of complement activation-induced P-aHUS was finally established for the patient, according to the positive result of the complement factor H (CFH). Active decision was made in the initial treatment. The plasma exchange was initiated early. "Small goals" were formulated in stages. The "small endpoints" were dynamically controlled in a goal-oriented manner to achieve continuous realization of the overall treatment effect through phased "small goals". On the 5th day of ICU treatment, the trend of microthrombosis in the patient was controlled, organ function damage was improved, and the patient was transferred out of the ICU. It is possible to reach a favorable clinical outcome for critically ill patients by applying a critical care mindset to quickly integrate diagnostic and therapeutic strategies, accurately identifying the triggers and causes that led to the progression of the disease, and using critical care medical techniques for early and effective intervention.
Humans ; Female ; Pregnancy ; Adult ; Atypical Hemolytic Uremic Syndrome/therapy* ; Intensive Care Units ; Pregnancy Complications, Hematologic/therapy* ; Critical Care

Atypical hemolytic uremic syndrome (aHUS) is a thrombotic microangiopathy characterized by microangiopathic hemolytic anemia, thrombocytopenia, and multi-organ damage, with the kidneys being predominantly affected. aHUS results from dysregulation of the complement alternative pathway, triggered by factors including infection, pregnancy, and surgery, among others. Therefore, complement inhibitors play a crucial role in the treatment of aHUS by blocking abnormal activation of the complement system and improving patients' prognosis. This consensus, developed by the Multidisciplinary Consensus Working Group on Atypical Hemolytic Uremic Syndrome Diagnosis and Treatment, is based on the latest literature and guidelines, discusses the pathogenesis, diagnosis and differential diagnosis, and treatment strategies for aHUS, and provides a guide and reference for the standardized diagnosis and management of aHUS in China.
Humans ; Atypical Hemolytic Uremic Syndrome/therapy* ; Consensus ; Diagnosis, Differential ; Prognosis

Antibodies, Monoclonal, Humanized/therapeutic use* ; Atypical Hemolytic Uremic Syndrome/drug therapy* ; Humans

Antibodies, Monoclonal, Humanized ; therapeutic use ; Atypical Hemolytic Uremic Syndrome ; drug therapy ; surgery ; China ; Humans ; Kidney Transplantation ; Male

OBJECTIVETo investigate the clinical characteristics, renal pathology, treatment and prognosis of children with atypical hemolytic uremic syndrome associated with H factor antibody.

METHODFour children less than 18 yr of age admitted from Nov. 2010 to May 2011 in Peking University First Hospital were included. They all met the criteria for atypical hemolytic uremic syndrome and with positive serum anti factor H antibody. They aged from 5 to 11 yr. Data on clinical manifestations, renal pathology, treatment and prognosis were analyzed.

RESULTAll of the 4 cases had gastrointestinal symptoms such as vomiting, abdominal pain, or abdominal distension. None of them had diarrhea. Two children had hypertension. One child had episodes of convulsion. One child had history of atypical hemolytic uremic syndrome. All of them had low serum complement C3. Three of them had low serum factor H (38.0, 88.4, 209.4 mg/L). All of them had serum antibody to factor H (1: 7 068, 1: 1 110, 1: 174, and 1: 869). Three of them received renal biopsy, all of them showed thrombotic microangiopathy. All of them were treated with steroid combined with mycophenolate mofetil. Two children received plasma exchange. They were followed up for 8 to 29 months. The renal function became normal and proteinuria relieved in all of them. The serum factor H concentration increased to 405.8, 155.8 and 438.4 mg/L, respectively. The titer of anti factor H antibody decreased to 1: 119, 1: 170, 1: 123, and 1: 674, respectively.

CONCLUSIONGastrointestinal symptom is common in children with atypical hemolytic uremic syndrome associated with H factor antibody. Hypocomplementemia was observed in all of them. Steroid combined with mycophenolate mofetil seemed to be effective for them. The monitoring of serum factor H and antibody to factor H may help diagnosis and treatment.

Atypical Hemolytic Uremic Syndrome ; Autoantibodies ; blood ; immunology ; Child ; Child, Preschool ; Complement Factor H ; immunology ; Creatinine ; blood ; Female ; Hemolytic-Uremic Syndrome ; drug therapy ; immunology ; pathology ; Humans ; Kidney ; pathology ; physiopathology ; Kidney Function Tests ; Male ; Mycophenolic Acid ; administration & dosage ; analogs & derivatives ; therapeutic use ; Plasma Exchange ; Prednisolone ; administration & dosage ; therapeutic use ; Prognosis ; Retrospective Studies