We read with interest the recent article on renal complications in children with hematotoxic snakebite by Islam, et al. [1]. We herein wish to raise some pertinent issues to assist in better understanding of this article.

(i)    Though the aim of the study was to ascertain clinical and laboratory indicators predicting acute kidney injury (AKI) “early” in children with snakebite envenomation; these predictors have neither been mentioned in the results nor in tables, unlike an earlier study [2], where various clinical and laboratory parameters were reported as predictors.

(ii)   There is no mention of baseline hemoglobin, maximum fall in hemoglobin, serum lactate dehydrogenase, evidence of myoglobinuria, hemo-dynamic status, cardiac dysrhythmias, cardiac dysfunction, evidence of adrenal hemorrhage, blood pressure, creatinine etc. which would have helped interpret the results better. These would have looked at creating a list of predictors of renal complications too [2]. Similarly, AKI could have been due to numerous other confounders like shock, dehydration, nephrotoxic antibiotics adminis-tration etc., which have not been detailed. Similarly, whether drug dose adjustments were made in those with AKI has also not been mentioned.

(iii)  AKI was appropriately defined based on the Kidney Disease: Improving Global Outcomes (KDIGO) criteria [3]. However, these patients were then followed up for 6 months [1], the reason for which is not clear, because for labelling chronic kidney disease, a 3-month follow-up would have been enough.

(iv)  Though one of the criteria for dialysis mentioned in this study was hyperkalemia, but the reason why medical management was not considered as an option is not apparent. Similarly, other reasons for dialysis like uremia, refractory metabolic acidosis too may have been indications for dialysis in these patients, which probably have not been included.

(v)   It was mentioned in the methodology that “peritoneal dialysis was done in the institution and hemodialysis in a referral hospital”. Whether these children were excluded or followed up is not clear. Details of how these children were followed up are missing. How many of these children who underwent dialysis developed ‘permanent renal damage’ at the 6-month follow up too has not been mentioned by authors, which could have been new information for the readers.

(vi)  Similarly, it is not clear as to whether the authors had taken the AKI stage at presentation or the maximum AKI stage as per the KDIGO guidelines during the hospital stay.

(vii) What were the indications and timing for the renal biopsy? Was doing a renal biopsy in the setting of an AKI reasonably justified and ethically correct? Snake-bites being medicolegal cases, it looks improbable that a renal biopsy was possible in 100% of the children who died but in only 81.4% of those who survived.

(viii) It is mentioned that 59 out of 364 children (16.2%) had “permanent renal damage” [1]. This is inappropriate as the denominator should exclude the deaths as permanent renal damage can be assessed only in those who survived the episode. So, we feel that the 16 children who succumbed should have been excluded, thus increasing the percentage of children with permanent renal damage to 16.9%.

(ix)  We presume that the median number of vials of anti-snake venom (ASV) used in both groups have been mentioned in Table I [1]. It may have been appropriate to have also mentioned the mean value, which would have added more clarity to the renal outcomes.

(x)   In the results, the authors state “our model can correctly predict 67.2-78.9% variation in AKI and 53.1-61.7% variation in mortality.” However, it is unclear which model they are referring to?

(xi)  The authors have mentioned mean “bite to ASV administration time” as 36.4 (5.9) minutes which seems practically difficult as their study population included patients from faraway places like the neighboring states of Bihar and Jharkhand. Besides, the whole blood clotting time itself takes 20 minutes to process after which the ASV must have been administered as per standard practice, which further delays the time to ASV administration. Hence, the mentioned time does not appear to be possible in these settings, as also seen in a previous study from the same region where this interval was 270 minutes [4].

Acknowledgement: Dr Amit Kumar Satapathy, Associate Pro-fessor, Department of Pediatrics, for academic input and review.

Funding: None; Competing interest: None stated.

REFERENCES

1.  Islam K, Seth S, Roy A, Datta AK. Predictors of renal complications in children with hematotoxic snakebite. Indian Pediatr. 2020;57:427-30.

2.  Aye KP, Thanachartwet V, Soe C, Desakorn V, Thwin KT, Chamnanchanunt S, et al. Clinical and laboratory parameters associated with acute kidney injury in patients with snakebite envenomation: A prospective observational study from Myanmar. BMC Nephrol. 2017;18:92.

3.  Levin A, Stevens PE. Summary of KDIGO 2012 CKD guideline: Behind the scenes, need for guidance, and a framework for moving forward. Kidney Int. 2014;85:49 61.

4. Sarkhel S, Ghosh R, Mana K, Gantait K. A hospital based epidemiological study of snakebite in Paschim Medinipur district, West Bengal, India. Toxicol Rep. 2017;4:415 19.