The Beef Jerky Blues: Methemoglobinemia From Home Cured Meat

Acquired methemoglobinemia in a third trimester puerpera and her premature infant with sodium nitrite poisoning: A case report

BACKGROUND

The common cause of sodium nitrite poisoning has shifted from previous accidental intoxication by exposure or ingestion of contaminated water and food to recent alarming intentional intoxication as an employed method of suicide/exit. The subsequent formation of methemoglobin (MetHb) restricts oxygen transport and utilization in the body, resulting in functional hypoxia at the tissue level. In clinical practice, a mismatch of cyanotic appearance and oxygen partial pressure usually contributes to the identification of methemoglobinemia. Prompt recognition of characteristic mismatch and accurate diagnosis of sodium nitrite poisoning are prerequisites for the implementation of standardized systemic interventions.

CASE SUMMARY

A pregnant woman was admitted to the Department of Critical Care Medicine at the First Affiliated Hospital of Harbin Medical University due to consciousness disorders and drowsiness 2 h before admission. Subsequently, she developed vomiting and cyanotic skin. The woman underwent orotracheal intubation, invasive mechanical ventilation (IMV), and correction of internal environment disturbance in the ICU. Her premature infant was born with a higher-than-normal MetHb level of 3.3%, and received detoxification with methylene blue and vitamin C, supplemental vitamin K1, an infusion of fresh frozen plasma, as well as respiratory support via orotracheal intubation and IMV. On day 3 after admission, the puerpera regained consciousness, evacuated the IMV, and resumed enteral nutrition. She was then transferred to the maternity ward 24 h later. On day 7 after admission, the woman recovered and was discharged without any sequelae.

CONCLUSION

MetHb can cross through the placental barrier. Level of MetHb both reflects severity of the sodium nitrite poisoning and serves as feedback on therapeutic effectiveness.

Nitrites: An Old Poison or a Current Hazard? Epidemiology of Intoxications Covering the Last 100 Years and Evaluation of Analytical Methods

In recent times, there has been a concerning and noteworthy rise in the global use of sodium nitrite for suicidal purposes. This is facilitated either through the employment of specialized "suicide kits" or by acquiring sodium nitrite through alternative means. Additionally, another occurrence contributing to nitrite poisoning is the recreational utilization of nitrites in the form of volatile aliphatic esters of nitrous acid, commonly referred to as "poppers". Based on current available papers and reports on the subject of nitrates, nitrites, and poppers intoxications, an epidemiological analysis and evaluation of analytical methods were performed. A total of 128 papers, documenting a collective count of 492 intoxication cases, were identified. Additionally, in order to complete the epidemiological profile of nitrite poisoning, the authors briefly examined six cases of nitrite intoxication that were under investigation in our laboratory. Furthermore, a review of nitrite poisoning cases over the past 100 years shows that the old poison is still in use and poses a substantial risk to society.

Rising incidence and high mortality in intentional sodium nitrite exposures reported to US poison centers

INTRODUCTION

Sodium nitrite is an oxidizing agent capable of producing profound methemoglobinemia. Large quantities of sodium nitrite can be purchased online, and recent literature has identified several cases of intentional self-poisoning, including multiple cases of mortality. This has raised concern that intentional sodium nitrite poisoning and resultant severe methemoglobinemia may be increasing in incidence and could represent a substantial public health threat.

MATERIALS AND METHODS

This study used data obtained from the National Poison Data System (NPDS) to evaluate the incidence and mortality rate of intentional sodium nitrite poisoning of suicidal intent reported to US poison centers over a five-year period. Patient demographics, exposure characteristics, treatments administered, and patient outcomes were analyzed. Temporal patterns in exposure were also investigated.

RESULTS

Forty-seven cases were identified in the NPDS database, of which three were excluded due to lack of outcome data. Median patient age was 23 years, 52% of patients were female and 86% of exposures occurred at the patient's residence. Serious outcomes were observed in 84% of cases, 77% of patients included were treated with methylene blue and 30% of patients died. No intentional sodium nitrite exposures were reported in the first two years studied, but we observed an increase in the incidence of exposures reported through the remainder of the investigation period.

DISCUSSION/CONCLUSIONS

The incidence of intentional self-poisoning with sodium nitrite has been increasing since 2017. Many of these exposures result in toxicity requiring antidotal therapy, and a high mortality rate was observed. Recent literature indicates that this trend may be the result of ready access to this poison through online vendors combined with recommendations shared in online communities that sodium nitrite be used as an effective method of suicide. Further study is needed to better characterize this phenomenon and develop public health interventions to prevent future morbidity and mortality.