Pediatrics practice tests with answers: 50 questions for exam preparation

The vast majority of invasive meningococcal disease cases worldwide are caused by five serogroups: A, B, C, Y, and W-135. Modern polysaccharide and conjugate vaccines are specifically directed against these serogroups.

The Frankfort (auricular-orbital) horizontal is a standard anthropometric plane passing through the lowest point of the left orbital margin and the highest points of the external acoustic meatuses (or upper margins of the tragus).

The cortical part of the vestibular analyzer is located in the temporal lobe of the cerebral cortex, and the cerebellum is the main central organ for movement coordination and balance maintenance.

In children of the third year of life, the need for daytime sleep is met by a single rest period, which normally lasts about 2–2.5 hours for full recovery of the nervous system.

At 6 months of age, a child may not yet have confident trunk control for independent sitting. Feeding in an adult's arms provides the necessary support with gradual introduction to the high chair as the skill develops.

Hemolytic anemias share a common feature: shortening of the erythrocyte lifespan due to their premature and accelerated destruction (hemolysis).

Diamond-Blackfan anemia is a congenital pure red cell aplasia characterized by isolated suppression of erythropoiesis, whereas Fanconi anemia presents with pancytopenia involving all hematopoietic lineages.

Fresh frozen plasma contains the full spectrum of blood coagulation factors and is used to replenish their deficiency in consumption coagulopathy (DIC syndrome), which may complicate intravascular hemolysis.

Lactoferrin binds iron in breast milk and interacts with specific receptors in the infant's intestine, ensuring the absorption of approximately 50% of this trace element.

Oral iron preparations can increase oxidative stress and alter the intestinal microbiome, precipitating flares of inflammatory bowel disease (such as ulcerative colitis). Therefore, in the presence of active mucosal inflammation, intravenous iron is the treatment of choice.

According to international classification criteria for systemic lupus erythematosus (SLICC, EULAR/ACR), persistent proteinuria greater than 0.5 grams per 24 hours is considered a reliable sign of lupus nephritis.

The peripheral (rim) antinuclear factor fluorescence pattern is caused by antibodies to native double-stranded DNA (anti-dsDNA), which are a highly specific marker for systemic lupus erythematosus.

Crampy abdominal pain, vomiting, and gastrointestinal bleeding in hemorrhagic vasculitis are caused by hemorrhages into the intestinal wall and mesentery, which constitutes the clinical picture of abdominal syndrome.

Hemorrhagic syndrome and decreased blood cell counts require the exclusion of primary vasculitides, autoimmune platelet destruction (ITP), and antiphospholipid syndrome, which share similar clinical and laboratory manifestations.

Abacterial verrucous endocarditis developing in systemic lupus erythematosus and antiphospholipid syndrome is eponymously known as Libman-Sacks endocarditis. It is characterized by the formation of immune thrombotic masses on the valves without the participation of an infectious agent.

Fetal infection in the first trimester (during organogenesis) has a teratogenic effect and leads to true malformations. Infection in the third trimester causes a generalized inflammatory process with internal organ involvement, but without disrupting their organogenesis.

The Paul-Bunnell and Hoff-Bauer reactions detect heterophile antibodies (IgM) that appear in the blood of patients with infectious mononucleosis and are capable of agglutinating erythrocytes of various animals (sheep, horse).

In Russian clinical practice, the severity of infectious mononucleosis, like most other infectious diseases, is traditionally categorized into mild, moderate, and severe forms.

There are no reliable vaccines against herpes simplex for mass use; therefore, compliance with personal hygiene rules and barrier contraception remain the mainstay of infection prevention.

Varicella-zoster virus is highly contagious and is transmitted primarily via airborne droplets during coughing, sneezing, or talking, and can travel significant distances with air currents.

Secondary sore throats occur as a manifestation of systemic infectious diseases (diphtheria, scarlet fever, infectious mononucleosis) or blood disorders (leukemias, agranulocytosis).

Nonspecific prevention aims to increase the body's overall resistance, which is achieved through conditioning methods, a balanced diet, and maintaining a proper work-rest schedule.

In follicular tonsillitis, suppurating follicles shine through the hyperemic tonsillar mucosa as small yellowish-white dots, metaphorically referred to as the "starry sky" sign.

Chronic foci of infection in the oral cavity and nasopharynx (carious teeth, sinusitis) serve as a permanent reservoir of pathogenic flora. Their timely treatment prevents downward infection of the palatine tonsils and relapses of tonsillitis.

According to B.S. Preobrazhensky's classification, primary tonsillitis is divided into catarrhal, follicular, lacunar, and necrotic forms. This division reflects the sequence and depth of the inflammatory process in the lymphoid tissue of the tonsils.

Meningism is a toxic irritation of the meninges against the background of high fever and intoxication, in which meningeal signs are detected, but the composition of the cerebrospinal fluid remains normal.

The highest susceptibility to meningococcus is observed in young children due to the immaturity of the immune system, which is why the age group under 5 years accounts for the vast majority of cases.

Purulent bacterial meningitis is characterized by pronounced pleocytosis in the cerebrospinal fluid with a sharp predominance of neutrophils, reflecting an acute inflammatory reaction to a bacterial infection.

Meningococcal nasopharyngitis proceeds without systemic toxemia and damage to the cerebral membranes, therefore the administration of oral antibacterial agents is sufficient for pathogen eradication.

In 1965, the World Health Organization recommended using the term "meningococcal infection" to combine various clinical forms of the disease (nasopharyngitis, meningitis, meningococcemia) under a single diagnosis.

In structural damage to the hemispheres (e.g., in extensive stroke), coma is accompanied by focal neurological deficits, most often asymmetrical. Brainstem reflexes remain preserved until a dislocation syndrome develops.

The ascending reticular activating system is a complex of neurons located predominantly in the upper parts of the brainstem (pons and midbrain) and non-specific thalamic nuclei, which maintain the level of cortical arousal.

Blood pressure measurement on both arms is a basic physical examination screening method that allows for the rapid suspicion of aortic dissection or subclavian steal syndrome, which may be the cause of altered consciousness.

Carbon monoxide poisoning leads to the formation of carboxyhemoglobin, which gives tissues a cherry-red color, while atropine causes marked dilation of skin capillaries, also resulting in skin flushing.

Lessaer's suspension sign is a specific meningeal sign for infants in their first year of life. When the meninges are irritated, the infant reflexively pulls their legs toward the abdomen and holds them in this position when lifted by the armpits.

The morphological substrate of rapidly progressive glomerulonephritis is extracapillary proliferative glomerulonephritis, in which cellular "crescents" formed by proliferating Bowman's capsule epithelium and macrophages are present in more than half of the glomeruli.

The phospholipase A2 receptor (PLA2R) is expressed on the surface of podocytes, making them the target for autoantibodies followed by the formation of subepithelial immune complexes.

A rapid decline in the glomerular filtration rate with the development of renal failure over weeks or months is characteristic of extracapillary glomerulonephritis, accompanied by the formation of glomerular "crescents".

Minimal change disease belongs to non-proliferative glomerulopathies, as there is no increase in the number of cells within the glomeruli. The primary pathogenetic mechanism is podocyte injury, leading to marked proteinuria without cellular proliferation.

Acute poststreptococcal glomerulonephritis is caused by the deposition of immune complexes in the renal glomeruli. On immunofluorescence microscopy, these deposits (IgG and the C3 complement component) produce a characteristic granular staining pattern resembling a "starry sky".

Consuming a small amount of plain water at room temperature 15–20 minutes before a meal reflexively stimulates gastric juice secretion and prepares the digestive tract for food intake.

It is not recommended to add salt to complementary foods for infants under one year of age, as this creates an excessive load on immature kidneys and disrupts the development of proper taste habits.

To maintain lactation during mixed feeding, the formula is always given only after the infant has emptied both breasts, in order to maximize breast milk production.

It is recommended to include lean fish in the diet of young children because it is easier to digest and less likely to cause allergic reactions. Fatty varieties create an excessive load on the child's immature digestive system.

By 10 months of age, the child has teeth and chewing skills are developing, so instead of meat puree, meatballs are introduced into the diet to stimulate the chewing apparatus and gastrointestinal motility.

The DTaP vaccine contains adsorbed tetanus toxoid, which ensures the development of specific antitoxic immunity against tetanus.

The glossopharyngeal nerve (along with the vagus nerve) innervates the muscles of the pharynx and larynx; therefore, damage to its nuclei in the medulla oblongata leads to impaired swallowing (dysphagia) and phonation (dysphonia).

Patients undergoing maintenance hemodialysis are exposed to frequent invasive procedures and contact with equipment and blood products. This places them in a high-risk group for bloodborne infections, including HIV.

The development of acute delta infection in a patient already suffering from chronic hepatitis B or who is an HBsAg carrier is classified as a superinfection. Such a condition often occurs in severe, fulminant forms with pronounced cytolytic syndrome and rapid development of liver failure.

Upon reactivation, the varicella-zoster virus persisting in sensory ganglia spreads centrifugally along the axons of nerve cells to the innervated skin area, causing the clinical presentation of herpes zoster.