Infectious Diseases Test Questions with Answers: 50 Questions for Exam Preparation

The term "status praesens" translates from Latin as "present state" and in the case history denotes the data of the patient's objective physical examination at the time of the visit.

Motor innervation of the tongue muscles is provided by the hypoglossal nerve (cranial nerve XII), therefore its lesion or involvement of its nuclei causes deviation, tremor, and restricted mobility of the tongue.

Mediterranean spotted fever is caused by Rickettsia conorii; therefore, IFA is used for its serological confirmation, detecting specific antibodies against the causative agents of tick-borne spotted fevers and other rickettsioses.

Motor fibers of the facial nerve (cranial nerve VII) provide innervation to all facial expression muscles.

The epidemic typhus pathogen multiplies in the louse intestinal epithelium and is released into the environment exclusively with the insect's excreta. Human infection occurs when infected feces are rubbed into skin scratch marks.

The Wright test (standard tube agglutination test) is the classical and primary quantitative serological method for diagnosing brucellosis, confirming the presence of specific antibodies in blood serum.

The oculomotor nerve innervates the levator palpebrae superioris muscle, as well as the medial, superior, and inferior rectus, and inferior oblique muscles of the eye, paralysis of which leads to characteristic ophthalmoplegia.

Ixodid ticks are the main natural reservoir and vector of tick-borne encephalitis virus, transmitting the infection through their bite.

ELISA and IFA are standardly used for the serological diagnosis of Lyme disease to detect specific antibodies.

The primary affect (tache noire at the tick bite site) combined with regional lymphadenitis forms the primary complex, which is an early and highly specific sign of Mediterranean spotted fever.

Peripheral facial nerve palsy causes lagophthalmos (incomplete eyelid closure), making the physiological upward movement of the eyeball visible when attempting to close the eyes.

Unilateral vagus nerve palsy causes paresis of the soft palate muscles on the affected side, so during phonation, the healthy muscles pull the uvula toward their side.

Humans are the intermediate hosts for the malaria parasite, meaning asexual reproduction of the parasite occurs in the human body (tissue and erythrocytic schizogony), whereas the sexual cycle (sporogony) takes place in the mosquito.

The term "ischuria paradoxa" (paradoxical ischuria) refers to a condition in which the bladder is overfilled, spontaneous urination is impossible, yet urine constantly dribbles out involuntarily.

Borrelia species are naturally resistant to fluoroquinolones; therefore, drugs of this group are not used to treat Lyme disease. The drugs of choice are tetracyclines, penicillins, and cephalosporins.

The oculomotor nerve innervates most extraocular muscles, the levator palpebrae superioris muscle, and the sphincter pupillae; therefore, its lesion causes ptosis, mydriasis, and divergent strabismus.

In joint involvement (Lyme arthritis), anti-borrelia antibodies are locally synthesized within the joint; therefore, both blood serum and synovial fluid are examined to confirm the diagnosis.

Rabies virus exhibits marked neurotropism and penetrates peripheral nerve endings by binding to nicotinic acetylcholine receptors at the neuromuscular junctions.

Rabies virus is tropic to structures of the limbic system. Damage to the amygdala leads to disinhibition of autonomic and behavioral responses, which may manifest as hypersexuality, priapism, and spontaneous ejaculation.

Babes nodules are focal accumulations of microglial cells and lymphocytes forming around dead neurons during the development of viral encephalitis. Cytoplasmic inclusions within the neurons themselves are called Negri bodies.

Retrograde axonal transport (from the periphery to the neuron cell body) is carried out by motor proteins called dyneins, which move toward the minus end of microtubules. It is this mechanism that the rabies virus utilizes to invade the CNS.

Bulbar syndrome occurs when the nuclei or roots of the glossopharyngeal (IX), vagus (X), accessory (XI), and hypoglossal (XII) nerves located in the medulla oblongata (bulb) are damaged.

M protein is the major surface antigen and virulence factor of Streptococcus pyogenes (GAS), which inhibits phagocytosis and ensures adhesion to the epithelium.

Rabies affects the nuclei of the medulla oblongata responsible for swallowing and breathing, leading to muscle spasms when attempting to drink (hydrophobia).

Lyssaophobia is a neurosis-like condition (fear of contracting rabies) in which psychogenic symptoms disappear under anesthesia, unlike the organic nervous system damage seen in true rabies.

Erysipeloid is characterized by the development of local erythema on the hands following microtraumas from contact with infected meat or fish, while marked intoxication and fever are usually absent.

The rabies virus affects the nuclei of the bulbar group of cranial nerves (IX, X, XII), leading to painful reflex spasms of the pharyngeal and respiratory muscles upon swallowing attempts.

Smoothing of the nasolabial fold and lagophthalmos (inability to close the eye) are classic signs of peripheral palsy of the facial muscles innervated by the facial nerve.

The causative agent of erysipelas (group A beta-hemolytic streptococcus) is capable of transforming into L-forms that persist in skin macrophages. When immunity declines, they revert to the initial bacterial forms, causing recurrent inflammation.

Septicemia is characterized by pronounced intoxication, a hyperergic reaction of the body, and rapid development of infectious-toxic shock without the formation of secondary purulent foci. In contrast, septicopyemia proceeds with the formation of metastatic abscesses in various organs.

Eicosanoids (prostaglandins, thromboxanes, leukotrienes) are formed via enzymatic oxidation of 20-carbon polyunsaturated fatty acids. The main precursor of these mediators in the human body is arachidonic acid.

The main etiological cause of sepsis is opportunistic bacterial microflora (staphylococci, streptococci, enterobacteria, Pseudomonas aeruginosa). These microorganisms are extracellular parasites and cause generalized infection when immune reactivity is reduced.

Parasympathetic fibers responsible for pupillary constriction and its reaction to light run within the oculomotor nerve.

Urosepsis is most commonly caused by gram-negative enteric bacteria (Escherichia coli, Proteus, Klebsiella), as well as enterococci, Pseudomonas aeruginosa, and Candida species.

Monocytes, macrophages, and dendritic cells express CD4 receptors on their surface, but unlike T-lymphocytes, they do not die when the virus replicates, becoming a long-term tissue reservoir for it.

Albendazole is the primary drug for the treatment of intestinal and disseminated forms of microsporidiosis, as it effectively disrupts tubulin polymerization in the parasite's cells.

Kaposi's sarcoma, associated with human herpesvirus 8 (HHV-8), is included in the standard list of AIDS-defining conditions along with non-Hodgkin lymphomas and invasive cervical cancer.

The transmembrane glycoprotein gp41 penetrates the lipid envelope of the virion and forms the "stem" (stalk) of the HIV spike, to which the surface glycoprotein gp120 is non-covalently attached.

Detection of Varicella Zoster virus DNA in cerebrospinal fluid by PCR is the gold standard and the most sensitive diagnostic method for viral CNS involvement.

Cholestyramine is an ion-exchange resin that binds bile acids in the intestinal lumen, preventing their reabsorption. This helps reduce blood bile acid concentration and relieves pruritus in cholestasis.

LTR sequences (long terminal repeats) contain promoters, enhancers, and polyadenylation signals that ensure the transcription of viral genes and their integration into the host genome via viral integrase.

Characteristic nocturnal pruritus, paired arrangement of rash elements, and the presence of serpiginous burrows ("stitches") are pathognomonic for scabies caused by Sarcoptes scabiei.

Pneumocystis jirovecii is an atypical fungus tropic to the alveolar epithelium of the lungs, causing opportunistic pneumocystis pneumonia in immunocompromised individuals.

Paracetamol overdose depletes hepatic glutathione stores and leads to the accumulation of a toxic metabolite (NAPQI), resulting in massive hepatocyte necrosis and fulminant hepatic failure.

Alkaline phosphatase and gamma-glutamyl transferase are localized on the apical membrane of hepatocytes and the biliary epithelium; therefore, their activity in the blood increases sharply when bile outflow is impaired.

Cryptosporidiosis agents are excreted in the feces as thick-walled oocysts that already contain sporozoites and are immediately capable of infecting new hosts.

Herpes simplex virus type 2 (HSV-2) is tropic to the mucous membranes of the genitals and, following primary infection, retrogradely migrates along sensory nerve fibers. Latent persistence of the virus occurs in the sacral ganglia innervating this region.

Hepatitis E virus genotypes 1 and 2 are strictly anthroponotic and are transmitted primarily via the fecal-oral route through contaminated water. Genotypes 3 and 4 can infect animals (pigs, wild boars) and cause zoonotic infections.

Immunoblotting detects antibodies to specific individual viral proteins, which reliably rules out false-positive results from screening ELISA.

The glycoprotein gp41 is a transmembrane viral protein that, after gp120 binds to receptors, undergoes a conformational change and ensures the fusion of the viral envelope with the cell membrane.