Incidence and outcome of laryngeal edema and rhabdomyolysis after ingestion of black rock

Black rock, Kala Pathar or ParaPhenyleneDiamine (PPD), is an aromatic amine widely used as a hair dye ingredient and is also used in textile industries. However, when ingested, PPD is highly toxic resulting in angioneurotic edema, rhabdomyolysis, acute kidney injury, toxic hepatitis, and myocarditis with a high mortality rate. This study aimed to evaluate the incidence and outcome of laryngeal edema and rhabdomyolysis after ingestion of PPD.

The current research was a cross-sectional study that was conducted at Aswan University Hospital, Aswan, Egypt, from December 2021 to December 2022. It consisted of 100 people who attempted suicide by ingesting black rock. All patients underwent general examinations and investigations, including complete blood count, urea, creatinine, creatine phospho kinase, alanine aminotransferase, aspartate aminotransferase, calcium, uric acid, phosphorus, urine analysis, and electrocardiography.

The current study consisted of 15 males and 85 females; the most common presentation was stridor (88%) followed by muscle weakness (50%). Twelve percent of patients with stridor required tracheostomy while 14% required tracheal intubation. Regarding the complications of PPD ingestion, the incidence of hepatic injury was (97%) and acute kidney injury (14%) five of them required hemodialysis, with a mortality rate of 13%. Cardiac arrhythmias were noticed in the form of sinus tachycardia (24%), sinus bradycardia (3%), atrial fibrillation (5%), ventricular fibrillation (6%), and ventricular tachycardia (7%). Our study found a significant positive correlation between creatine phosphokinase, muscle weakness, and acute kidney injury (P = 0.005). Whereas a significant positive correlation was noted between stridor, hospital stay, and mortality rate (P = 0.000), (P = 0.003), respectively. Moreover, a significant positive correlation was found between tracheotomy, mortality rate, and hospital stay (P = 0.000).

PDD toxicity is more frequent in younger females. The intoxication from the black rock is increasingly used in suicide attempts and vital organs are usually affected especially the kidney, liver, and heart causing morbidity and mortality.