Which tissues are primarily involved in the pathological process of ARI?

The epithelium of the respiratory mucosa is primarily affected, serving as the site of viral replication and the development of alterative changes.

What vascular changes characterize inflammation in viral infections?

Marked vascular congestion, increased vascular permeability, plasmatorrhagia, and diapedetic hemorrhages within the inflammatory focus.

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Acute Viral Respiratory Infections (ARI)

*Infektiose respiratoriae acutae*

For medical students2 min readUpdated 2026-10-10

Acute viral respiratory infections are a widespread group of infectious diseases affecting the respiratory tract. Pathology studies the specific tissue and organ alterations that occur during these infections.

PathogensVarious respiratory viruses

LocalizationRespiratory tract

PathogenesisInflammatory mucosal alterations

MorphologyAlteration and exudation

General Characteristics and Etiology

Acute respiratory viral infections encompass a group of respiratory pathologies sharing similar transmission mechanisms and clinical manifestations. Viral agents show a high tropism for the respiratory tract epithelium, which determines the primary tissue alterations.

Pathogenesis and Morphological Changes

Pathogen entry into the epithelial cells of the respiratory tract.
Development of dystrophic and necrotic processes.
Inflammatory response with microcirculatory disturbances and exudation.

Alteration of the epithelium leads to a failure of mucosal protective functions and facilitates secondary bacterial colonization.

Clinico-Morphological Manifestations

The disease involves both the upper and lower respiratory tracts. Vascular congestion, edema, and cellular infiltration of tissues are observed, reflecting the classic stages of the inflammatory process.

Mnemonic

ARI: Alteration, Reaction, Inflammation, Infiltration.

Frequently asked questions

Which tissues are primarily involved in the pathological process of ARI?: The epithelium of the respiratory mucosa is primarily affected, serving as the site of viral replication and the development of alterative changes.
What vascular changes characterize inflammation in viral infections?: Marked vascular congestion, increased vascular permeability, plasmatorrhagia, and diapedetic hemorrhages within the inflammatory focus.

Go deeper

Mechanisms of viral cytopathic effects
Development of respiratory complications
Morphology of interstitial pneumonia
Immunohistochemical diagnosis of respiratory infections