Pediatric virus-associated phagocytic syndrome
Introduction
Introduction to pediatric virus-associated phagocytic blood cell syndrome Virus-associated hemophagocytics syndrome (VAHS), also known as systemic histiocytosis with obvious phagocytosis of blood cells, is a type of immune histiocytosis. The condition is associated with systemic viral infections and is characterized by high fever, rash, and cytopenia. basic knowledge Sickness ratio: 0.05% Susceptible people: young children Mode of infection: non-infectious Complications: pneumonia, renal failure
Cause
Pediatric virus-associated phagocytic blood cell syndrome
(1) Causes of the disease
It is related to infections such as Epstein-Barr virus, cytomegalovirus, herpes simplex virus, herpes zoster virus, adenovirus, Colung virus, hepatitis B virus, etc. The serum virus antibody titer is elevated from the child, and the virus culture is positive, biopsy, autopsy, etc. It has been confirmed that in addition to the above related viruses, VAHS may also be secondary to typhoid fever, miliary tuberculosis, staphylococcal sepsis, Gram-negative bacilli infection, brucellosis, malaria, kala-azar, mycoplasma infection, fungal infection, and The use of drugs such as phenytoin sodium caused reports of the disease.
(two) pathogenesis
This disease is related to viral infection. It is a systemic histiocytosis with obvious phagocytosis of blood cells. It is a kind of reactive histiocytosis. Reactive histiocytosis can be divided into two major infections and immunity. In this category, the symptoms are infective. Recently, Grierson et al found a higher proportion of children with lymph node hyperplasia (XLP) with this disease. Of the 161 children with XLP, 28 had VAHS.
Prevention
Pediatric virus-associated phagocytic blood cell syndrome prevention
At present, there is no preventive vaccine, and there are difficulties in the development of vaccines. Because there are too many types of viruses, it is impossible to control all types. For those who have close contact with the body or have a close contact with newborns, they can inject gamma globulin 3-6 ml or placenta. Globulin 6 ~ 9ml.
Complication
Pediatric virus-associated phagocytic blood cell syndrome complications Complications, pneumonia, renal failure
Multiple organ dysfunction can occur, pneumonia or pulmonary hemorrhage, DIC, renal failure, etc. can occur.
Symptom
Pediatric virus-associated phagocytic blood cell syndrome symptoms common symptoms night sweats high fever whole blood cells reduce lymph node enlargement renal failure coagulopathy
The clinical manifestations of virus-associated phagocytic blood cell syndrome are diverse, and the common clinical manifestations are as follows:
1. General characteristics: high fever, rash, night sweats, weight loss, hepatosplenomegaly, etc., broad-spectrum antibiotic treatment is ineffective, 1 to 8 weeks can be relieved.
2. Partial or whole blood cell reduction: Whole blood cell reduction is associated with tissue cell phagocytosis of blood cells, and Pirsch considers it to be the result of viral infection inhibiting bone marrow.
3. Multiple organ damage: liver function damage or coagulopathy, some cases may have central nervous system symptoms, lung infiltration, renal failure and other organ damage.
4. Pathological features: lymph node biopsy or spleen biopsy also showed tissue cell enlargement and phagocytosis of blood cells.
Examine
Examination of pediatric virus-associated phagocytic blood cell syndrome
Blood test
Hypoproteinemia, 2 globulin ratio increased, blood cholesterol concentration decreased, C-reactive protein was strongly positive, and lactate dehydrogenase increased LDH3 to LDH5 levels.
2. Bone marrow examination
Bone marrow smears showed that most of the histiocytosis cells were mature.
Specific manifestations are visible tissue cells phagocytizing red blood cells (mature and nucleated), white blood cells (multinuclear and lymph), platelets and blood cell debris.
The granules and erythropoiesis are low, the megakaryocytes are normal or over-produced, and the appearance and disappearance of phagocytic blood cells are synchronized with the activity and relief of the disease.
3. Pathogen examination
The vast majority of children with VAHS are secondary to EB virus infection, so the corresponding antibody titer of EB virus infection can be determined to confirm the diagnosis of Epstein-Barr virus infection.
At VAHS, lymphocyte changes in EB virus infection, with a decrease in CD8-positive suppressor T cells, significantly increased the OKT4/OKT8 ratio by 1.0 to 4.6, suggesting a manifestation of VAHS and a defect in the immune function of Epstein-Barr virus. The proportion and absolute number of CD8-positive cells in the acute phase of infectious mononucleosis (IM) associated with EB virus infection increased, resulting in a significant decrease in the CD4/CD8 ratio (mean 0.49 ± 0.20). Identification of infectious mononucleosis.
Diagnosis
Diagnosis and identification of pediatric virus-associated phagocytic blood cell syndrome
diagnosis
According to the clinical manifestations and laboratory findings, the diagnosis is based on the obvious phagocytic blood cell phenomenon in the bone marrow.
Differential diagnosis
Must be differentiated from histiocytosis with phagocytic blood cell phenomena.
