Shwachman-Diamond syndrome is a genetic pathology manifested by secretory insufficiency of the pancreas, bone marrow disorders and serious hematological changes. The first symptoms (diarrhea, flatulence, decreased appetite, dystrophy, skeletal deformity, anemia, etc.) are recorded at 5-6 months during the introduction of complementary foods. The main diagnostic measures: biochemical and general analysis of blood and feces, hormonal studies, ultrasound, CT and MRI of abdominal organs, radiography of the skeleton. Treatment is aimed at eliminating clinical signs and maintaining vital activity.
Shwachman-Diamond syndrome is a rare genetic disease characterized by a malfunction of the pancreas and bone marrow dysfunction. The disease is manifested by a comprehensive delay in development (mental, mental and physical), an increased susceptibility to infections is noted. The prevalence of the disease is 1:50,000 children born. The syndrome is somewhat more common in boys. The prognosis is extremely unfavorable, since most patients do not live up to 7 years.
The pathology was first described by Bodian and Sheldon in 1964 in patients with congenital pancreatic hypoplasia, growth retardation and pancytopenia. In the same year, Shvakhmon and Diamond studied in detail exocrine pancreatic insufficiency and bone marrow dysfunction in this disease. The variety of manifestations of the syndrome requires a coordinated interdisciplinary approach to the treatment of pathology with the participation of specialists in the field of gastroenterology, genetics, pediatrics.
The cause of the development of the Shwachman-Diamond syndrome is a genetic anomaly. The pathology is caused by a mutation of one of the sections of chromosome 7 (SBDS gene), it is inherited in an autosomal recessive type, that is, both parents must pass the defective gene to their child. Sporadic cases of Shwachman-Diamond syndrome are also recorded – in their etiology, an important role is assigned to the effects of mumps and Coxsackie viruses on the tissues of the embryo. Clinical signs begin to appear 5-6 months after birth.
Although the exact function of the SBDS gene has not been determined, its mutation causes developmental delay; fatty degeneration of pancreatic tissue; bone marrow hypoplasia, which leads to serious hematological changes.
Clinical signs of Shwachman-Diamond syndrome appear after the introduction of complementary foods (5-6 months). The first symptom of pathology is diarrhea, or rather, steatorrhea, which is characterized by a significant increase in the proportion of fat in the stool. Against the background of stool disorders, appetite decreases, flatulence appears. These signs are due to insufficient secretory function of the pancreas. In addition, other endocrine disorders are detected, the result of which is the development of subnanism – stunting. Bone tissue dystrophy gradually develops, the physical and mental development of the child is delayed. In most patients, bone deformity is recorded, accompanied by causeless fractures.
From the first day of the child’s life, an altered blood picture is determined: the number of neutrophils (neutropenia) decreases, the number of red blood cells (anemia) and platelets (thrombocytopenia) sharply decreases, all this is combined with hemorrhagic syndrome (increased bleeding on the background of clotting disorders). Patients are susceptible to the development of infectious diseases of various body systems (respiratory organs, urinary system, skin, etc.).
In mild form, the symptoms characteristic of the disease are not pronounced, with adequate therapy, such patients live up to 20 years. In severe form, clinical signs appear early and progress rapidly, any therapeutic measures do not give a positive effect, these patients die very early.
Diagnosis of the Shwachman-Diamond syndrome is not difficult, a pediatrician can suspect the presence of pathology during a preventive examination and the appearance of characteristic symptoms. The doctor carefully collects anamnesis, identifies chronic diseases, as well as cases of the syndrome in the next of kin. Since the first signs are associated with dyspeptic disorders, the pathology may be suspected by a gastroenterologist.
To make a final diagnosis, it is necessary to carry out instrumental and laboratory methods of examination: stool and blood analysis, hormonal studies, CT, MRI, abdominal ultrasound, radiography of the skeleton.
Analysis of fecal masses reveals steatorrhea, a general blood test – neutropenia, thrombocytopenia, anemia, sometimes pancytopenia – a decrease in the number of all blood cells. A biochemical blood test shows the state of metabolic processes, as well as the concentration and properties of enzymes.
CT, MRI, ultrasound of the abdominal cavity organs reveal changes in pancreatic tissue, these studies are also carried out to exclude other diseases of the digestive system. Bone radiography determines the degree of deformation of the skeleton. All patients are assigned to consult a neurologist, a geneticist with a molecular genetic analysis.
Treatment of Shwachman-Diamond syndrome is aimed at eliminating adverse symptoms and maintaining vital functions. All patients are prescribed a strict diet: limit fats, increase protein content. Substitution therapy is required to fill in the missing pancreatic enzymes. When infectious diseases appear, antibacterial drugs are prescribed. It is also necessary to restore the indicators of the blood picture; anemia is successfully amenable to therapy, other changes are difficult to correct. If a severe form of pathology and serious hematological disorders develop, chemotherapy and radiation therapy, bone marrow transplantation are performed.
The prognosis of the Shwachman-Diamond syndrome is extremely unfavorable. According to statistics, patients die at 7-10 years old, very rarely they live to 20 years. This is due to a strong decrease in immunity and the development of serious infectious diseases. In rare cases, the nature of the course of pathology changes towards improvement, as a rule, secretory insufficiency gradually decreases, but at the same time hematological disorders are not restored.