Post-Infectious Auto immune Hemolytic anemia

Dr.Ghaniya KC , Dr.C.Jayakumar

Three year old female child presented with Incidentally detected low Hb during rituneCBC one week back 
Hb- 6.1 gm/dl 
No h/o cough /vomiting /seziures/ loose stools,bleeding from any sites ,picca ,recurrent infections
Past History –
Three months ago had LRTI , CBC done Hb was mortal at that time
O/E : 
Child is active, not sick looking
Vitals stable 
Pallor + 
mild Icterus + 
No cyanosis , clubbing , lymphadenopathy, edema
Systemic examination: 
P/A – soft, non-tender , No hepatosplenomegaly. normal bowel sounds system examination was normal 
Investigations – 
Hemoglobin – 6.1 gm/dl.Platelets and WBC – normal

Peripheral smear – Macrocytic RBC , Polychromatophils + , Anisopoikilocytosis + , Microcytes + , Elliptpcytes + , Tear drop cells + 
Retic count – 23% 
Direct coomb’s test – 4+. 
ANA – IFA : negative
Eosin 5’ Maleamide : negative
Respiratory viral panel – negative 
Course : She was starred in Tab Folic acid 5mg and managed symptomatically. Her hemoglobin gradually improved to 8.1 mg/dl. 

She developed fever after one week.Hb dropped again from 9 to 7.5 gm/dl and was started on Oral Prednisolone 1mg/kg 
After starting steroids Hb improved to 10.1 gm%

Post -infectious autoimmune hemolytic anemia 

Post-infectious autoimmune hemolytic anemia (PIAIHA) is a condition where the immune system mistakenly attacks and destroys red blood cells following an infection. Here are the important points to consider:

1. Etiology and Pathophysiology

• Infections Triggering AIHA: Common infections associated with PIAIHA include viral infections (e.g., Epstein-Barr virus, Cytomegalovirus, HIV), bacterial infections (e.g., Mycoplasma pneumoniae), and less commonly, parasitic infections (e.g., malaria).
• Mechanism: The immune system produces antibodies that mistakenly target the red blood cells, leading to their destruction (hemolysis). This can be mediated IgG (warm agglutinin) or IgM (cold agglutinin) antibodies.

2. Clinical Presentation

• Symptoms: Fatigue, pallor, jaundice, dark urine, and possibly splenomegaly. In severe cases, symptoms of anemia may include tachycardia, dyspnea, and dizziness.
• Time Course: Symptoms typically appear a few days to weeks after the resolution of the initial infection.

3. Diagnosis

• Laboratory Findings:
• Hemolysis markers: Elevated lactate dehydrogenase (LDH), indirect bilirubin, and decreased haptoglobin.
• Direct Antiglobulin Test (DAT or Coombs Test): Positive in most cases, indicating the presence of antibodies bound to red blood cells.
• Blood Smear: May show spherocytes (indicating extravascular hemolysis) or fragmented cells.

4. Management

• Treat the Underlying Infection: If still present, addressing the infectious cause is crucial.
• Steroids: First-line therapy to reduce immune system activity. Prednisone is commonly used.
• Immunosuppressants: If steroids are ineffective, other immunosuppressive drugs like rituximab or cyclophosphamide may be considered.
• Blood Transfusions: May be necessary in severe anemia, though care is taken due to the risk of further hemolysis.
• Splenectomy: Considered in refractory cases, as the spleen is a major site of red blood cell destruction.

5. Prognosis

• Generally Favorable: Most patients respond to treatment, especially if the underlying infection is well-managed.
• Relapse Risk: There is a risk of relapse, particularly if exposed to the same or similar infections in the future.

6. Follow-Up

• Regular Monitoring: Patients should be regularly monitored for signs of recurrent hemolysis or anemia.
• Vaccinations: Ensure vaccinations are up to date, especially for infections that might trigger AIHA (e.g., pneumococcus, influenza).

In the case of autoimmune hemolytic anemia (AIHA), steroid treatment is usually initiated to reduce hemolysis (red blood cell destruction) and promote a response. The duration of steroid treatment in AIHA can vary depending on the individual’s response and the severity of the disease.

Typically, steroid treatment for AIHA may last:

1. Initial phase: 2-6 weeks – High-dose steroids are used to control acute hemolysis.
2. Tapering phase: 2-6 months – Steroid doses are gradually reduced to maintain a response while minimizing side effects.
3. Maintenance phase: 6-12 months or longer – Low-dose steroids may be continued to maintain a response and prevent relapse.

In some cases, steroid treatment may be needed for:

1. Short-term control of severe hemolysis
2. Bridging therapy until other treatments (e.g., rituximab, immunosuppressants) take effect
3. Long-term management of chronic AIHA

It’s essential to work closely with your hematologist to determine the optimal duration and dosage of steroid treatment for your specific case of AIHA. They will monitor your response, adjust treatment, and consider alternative therapies as needed.