A Forensic Case of Suicide Ingestion of Paraquat Herbicide: New Histological Insights and Revision of the Literature

Abstract

Paraquat (PQ) is one of the most widely used herbicides in the world, and poisoning is generally associated with accidental, suicidal, or homicidal events. Therefore, in the forensic context, PQ could be in various ways involved as a possible cause of death of a subject. However, even though its systemic toxicity is known, the biological effects exerted on individual viscera have been explored only to some extent, especially in case of victim's survival. Therefore, a case concerning a suicidal ingestion of PQ with survival of 3 days was deemed of interest. Clinical toxicological analyses confirmed acute PQ intoxication, and after the death of the victim, an autopsy was performed showing local and systemic signs of ingestion of a caustic substance. Histologic examination revealed marked cellular damage to the major viscera, particularly the gastroesophageal tract, liver, kidneys, and lungs, with initial alveolar fibrosis noted despite the patient's short survival. This finding represents a new element in the context of PQ lung injury, as it has not been previously documented in the literature. Thus, histological findings in lethal intoxications after survival can reveal specific peculiarities still unknown and, therefore, assume transversal relevance not only at forensic but also clinical level.

FIGURE 1

Autopsy visceral macroscopic pictures: in A, stomach with evident areas of hemorrhagic infiltration of the mucosa; in B, lungs with paler parenchyma areas alternating with other partially confluent red-purple areas; in C, left kidney with cortical layer characterized by multiple and small purpuric areas; in D, liver with focal hemorrhagic superficial areas and gallbladder containing dense blackish bile.

FIGURE 2

Microscopic pictures in H&E: in A, peribuccal skin with areas of detachment and ulceration (100×); in B, esophageal mucosa with necrotic-hemorrhagic lesions, ulcerations, and inflammatory infiltrates (100×). H&E, hematoxylin and eosin.

FIGURE 3

Microscopic pictures in H&E: gastric (A) and intestinal mucosa (B) with necrotic-hemorrhagic lesions and acute hemorrhagic infiltrates with areas of mucosal detachment (100×). H&E, hematoxylin and eosin.

FIGURE 4

Microscopic pulmonary pictures with H&E: in A, massive areas of pulmonary hemorrhage with alveolar flood, in the presence of severe edema (100×); in B, almost total destruction of the alveolar septa (200×), in presence of massive inflammatory infiltrate, as shown in the detail (400×); in C, alveolar septa thickened (100×), with detail of fibrosis and fibroblasts at higher magnification in D (400×). H&E, hematoxylin and eosin.

FIGURE 5

Microscopic pictures in H&E: in A, heart with evidence of multiple foci of interstitial hemorrhage (400×); in B, liver with diffuse foci of hepatocellular necrosis (400×). H&E, hematoxylin and eosin.

FIGURE 6

Microscopic pictures in H&E: in A, kidneys with evidence of multiple and diffuse hemorrhagic infiltrates and acute tubular necrosis in the context of inflammatory infiltrate (100×); in B, detail of bladder mucosa with marked hemorrhage (100×). H&E, hematoxylin and eosin.