Kids, colds, and complement: paroxysmal cold hemoglobinuria

Epstein-Barr Virus-induced Paroxysmal Cold Hemoglobinuria in a 17-Year-old Male

Paroxysmal cold hemoglobinuria is a rare autoimmune hemolytic anemia seen almost exclusively in children under 5 years of age after a viral illness. It is mediated by a biphasic polyclonal autoantibody against red blood cells, which causes severe hemolysis that typically self-resolves within 2 weeks without recurrence. While laboratory identification of the aforementioned antibody, the Donath Landsteiner antibody, would confirm this diagnosis, a negative test does not rule out this condition in the appropriate clinical context. We report on the rare occurrence of a severe presentation of paroxysmal cold hemoglobinuria in a 17-year-old male with Epstein-Barr virus infection.

Severe Acute Kidney Injury in Children as a Rare Complication of Paroxysmal Cold Hemoglobinuria

Paroxysmal cold hemoglobinuria (PCH) is a rare condition in childhood characterized by complement-mediated premature destruction of red blood cells. PCH is associated with intravascular hemolysis causing hemoglobinuria, which may result in acute kidney injury of various severity. We aimed to retrospectively analyze clinical and laboratory features of children with PCH-associated acute kidney injury received at tertiary Pediatric Hematology and Nephrology Center, University Motol Hospital, Prague, Czech Republic during the period 2016 to 2022. We present here 3 children with PCH-associated acute kidney failure requiring renal replacement therapy. We highlight the association of PCH with kidney disease. Renal parameters and urine examination should be regularly tested in all children with PCH.

Paroxysmal cold hemoglobinuria: A diagnostic dilemma in a paediatric patient

BACKGROUND

Autoimmune hemolytic anaemia is rare in the paediatric population. Differentiation of the underlying aetiology is complicated by heterogeneity in diagnostic criteria and testing strategies. Paroxysmal cold hemoglobinuria (PCH) is an uncommon form of paediatric autoimmune hemolytic anaemia. Identification of the causative biphasic hemolysin requires clinical recognition and access to the Donath-Landsteiner (DL) test.

CASE PRESENTATION

We report a young paediatric patient with no significant past medical history who presented with severe anaemia, jaundice, and dark urine following a respiratory illness. Initial laboratory evaluation showed a haemoglobin of 3.6 g/dL with plasma free haemoglobin 170 mg/dL (reference range <5 mg/dL), 3+ hemoglobinuria (reference range = 0), and direct antiglobulin testing (DAT) positive for complement component 3 (C3) only. Haemoglobin continued to decline following RBC transfusions using a blood warmer for presumed cold agglutinin syndrome. Subsequent testing at the reference laboratory revealed a DAT positive for C3 and immunoglobulin isotype G (IgG) and an eluate pan-agglutinin most consistent with a warm autoantibody, but the patient's anaemia was non-responsive to glucocorticoids and blood warmer cessation. However, a maximum cold agglutinin titre of 4 and absent thermal amplitude substantially weakened the evidence for the clinical significance of the cold autoantibodies. Consultation with the institutional transfusion medicine specialist prompted collection for the DL test, which demonstrated a definitive biphasic hemolysin consistent with PCH.

DISCUSSION

Conflicting clinical and immunohematologic evidence can obscure the aetiology of autoimmune hemolysis, including concurrent warm and/or cold autoantibodies. Clinical correlation, consultation with the institutional transfusion service, and access to specialised testing are essential to establish the correct diagnosis.

A single center experience for clinical evaluation of paroxysmal cold hemoglobinuria and Donath-Landsteiner testing

BACKGROUND

Paroxysmal cold hemoglobinuria (PCH) is a rare form of autoimmune hemolytic anemia (AIHA), mainly affecting children. The diagnosis and management are challenging due to similarities to other causes for AIHA and limited availability to Donath-Landsteiner (DL) testing.

STUDY DESIGN AND METHODS

In this single-center retrospective study, we aimed to characterize the clinical presentation and outcomes of PCH patients, defined as having positive Donath-Landsteiner antibodies, compared to a cohort of AIHA patients.

RESULTS

DL-positive patients were observed to have higher lactate dehydrogenase levels and lower reticulocyte counts compared to DL-negative patients, although this was not statistically significant. We also observed that using steroids in DL-positive patients did not significantly impact their recovery.

DISCUSSION

Our findings support the limited published data on PCH patients and further prompt larger multicenter studies to further characterize these patients so that they are more readily identified, especially in centers where DL antibody testing is not readily available.

A Case of Childhood Severe Paroxysmal Cold Hemoglobinuria with Acute Renal Failure Successfully Treated with Plasma Exchange and Eculizumab

We describe the case of a 4-year-old female who presented with sepsis and disseminated intravascular coagulation (DIC), developed ongoing intravascular hemolysis with acute renal failure from suspected pigment-induced acute tubular necrosis necessitating continuous renal replacement therapy (CRRT) for five days followed by four episodes of intermittent hemodialysis (iHD), and was subsequently diagnosed with paroxysmal cold hemoglobinuria (PCH). She was successfully treated with plasma exchange and eculizumab, a humanized monoclonal antibody targeting complement protein C5, and demonstrated significant improvement of hemolysis and recovery of renal function.

A Case of Paroxysmal Cold Hemoglobinuria Possessing Moderate Paroxysmal Nocturnal Hemoglobinuria-Type Erythrocytes

Patient: Female, 82-year-old

Final Diagnosis: Paroxysmal cold hemoglobinuria

Symptoms: Anemia

Medication:—

Clinical Procedure: —

Specialty: Hematology

Allo-anti-M: Detection peaks around 2 years of age, but may be attenuated by red blood cell transfusion

BACKGROUND

Anti-M is frequently observed as a naturally occurring antibody of little clinical significance. Naturally occurring anti-M is often found in children although the specific triggers of production, persistence, and evanescence of anti-M have yet to be elucidated.

METHODS

In a retrospective, multicenter, nationwide cohort survey conducted from 2001 to 2015, alloantibody screening was performed before and after transfusion in 18,944 recipients younger than 20 years. Recipients were categorized into six cohorts based on their age at transfusion; within and among these cohorts, allo-anti-M was analyzed in regard to its production, persistence, and evanescence.

RESULTS

In 44 patients, anti-M detected before and/or after transfusion was an age-related phenomenon, with a median age of 2 years and an interquartile range of 1-3 years; anti-M was most frequently detected in a cohort of children 1 to <5 years (0.77%, 31 of 4035). At least five patients were presumed to have concurrent infections. Among 1575 adolescents/young adults (15 to <20 years), no anti-M was detected. Of 29 patients with anti-M prior to transfusion, the antibody fell to undetectable levels in 17 recipients (89.5%, of whom at least 13 received only M-negative red cells) after anywhere from 5 days to 5.8 years; anti-M persisted in 2, and was not tested in 10. Only 15 recipients (0.08%) produced new anti-M after transfusion.

CONCLUSION

Naturally occurring anti-M is a phenomenon of younger ages, predominantly between 1 and 3 years. After transfusion, it often falls to undetectable levels.

Paroxysmal cold hemoglobinuria successfully treated with complement inhibition

This is the first-ever demonstration of successful treatment of paroxysmal cold hemoglobinuria using the complement inhibitor eculizumab.