Background of the participants

A total of 108 respondents participated in the survey and 95.4% had experience in managing children with NDM (Q41). The characteristics of all participants are displayed in Table 1.

Table 1 Characteristics of the participantsDiagnostic Approaches

After reviewing the case scenario, 60.2% of respondents considered that the diagnosis of NDM could be confirmed, 38% thought that the diagnosis was suspected, and 1.8% felt that the infant did not meet the criteria for NDM (Q7). The majority (82.4%) stated that it is impossible to predict at presentation whether NDM will be permanent or transient (Q8).

Treatment Practices

For initial treatment, 88% of respondents suggested starting insulin therapy, 11.1% recommended trying oral SU, and 0.9% advocated for diet and caloric restriction (Q9). Detailed responses regarding insulin dosage, dilution, and regimen are displayed in Table 2 (Q10–15). Most respondents (80.6%) would use continuous glucose monitoring (CGM) in infants with NDM (Q16). Supplemental Figs. 2–6 show the family and personal history aspects that participants would collect (Q17–19).

Table 2 Dose, dilution, and regimen of insulin treatment (the percentage of answers provided is highlighted in bold)Genetic Testing

Nearly all respondents (98.1%) agreed that all infants with NDM should undergo genetic testing. The preferred cut-off for genetic testing was 6 months for 50.9%, 9 months for 15.7%, 12 months for 30.6%, and 24 months for 0.9% of the respondents (1.9% would not perform genetic testing in all patients) (Q20). Table 3 displays the responses to question Q20–24 about the management of genetic testing.

Table 3 Responses to question Q20–24 about the management of genetic testing

Most participants (73.1%) would not try SU before genetic testing, and 58.3% would not use SU while awaiting results (Q25–26). Nonetheless, 68.5% would try SU if genetic testing facilities were unavailable (Suppl. Fig. 7 displays data split into high vs. low incidence countries) (Q27). The preferred dose for successful SU treatment of 0.31–0.6 mg/kg ranked first (45.4% of the participants), 0.01–0.3 mg/kg second (26.9%), and above 0.6 mg/kg third (12%) (15.7% of participants did not suggest any dose) (Q28).

Education and Confidence

Knowledge of various NDM-related topics is illustrated in Fig. 1 (Q33). Only 37% of respondents received specific training on the diagnosis and management of NDM (Q34). Despite that, 97.2% indicated that acquiring specific knowledge and practical skills related to NDM should be mandatory for diabetologists/endocrinologists (Q35). Regarding confidence in managing NDM, 18.5% felt completely confident, 37% fairly confident, 31.5% somewhat confident, and 13% slightly or not confident at all (Q42).

Fig. 1

Answers of the participants to the question “Can you describe the knowledge you have of the following topics related to neonatal diabetes mellitus (NDM)?” split into high vs. low incidence countries. SU Sulfonylurea

Guidelines and Training

Guidelines for the management of NDM were available in 35.2% of the participants' units (Q36). Of the total participants, 60.2% were aware of ISPAD guidelines, 25.9% were familiar with both ISPAD and ESPE guidelines, 12% were unaware of any international guidelines and 1.9% of the participants used other international society guidelines (Q37). Interdisciplinary guidelines would be appreciated, as 88.9% of participants do not know any (Q39). Online training, such as webinars, was the preferred method for education about NDM (44.4%), followed by dedicated sessions during international scientific meetings (38.9%). Websites, e-mails, or other tools were considered appropriate for teaching about NDM by 10.2% of the participants (Q40).

NDM Incidence in the Country of Practice

No differences were found based on NDM incidence in the country of practice concerning experience and clinic features (supplementary Table 2). Participants from high-incidence countries would start treatment more frequently with MDI than with CSII (55.3% and 28.9%, respectively) than participants from low-incidence countries (21.4% and 68.6%, respectively) (p < 0.001) (Q12), and would use CGMS less frequently (60.5% and 91.4%, respectively, p < 0.001) (Q16). Only 63.2% of respondents from high-incidence countries require genetic testing (90.0% in low-incidence countries, p = 0.003) (Q21). Participants from high-incidence countries would try SU before genetic testing in 42.1% of the cases versus 18.6% of the other participants (p = 0.008) (Q25). Supplemental Figure 1 shows the rate of the most frequent cause of NDM split into high- and low-incidence countries (Q30). Wolcott–Rallison syndrome was the most frequent cause (18.4%) in high-incidence countries (0% in low-incidence countries; p < 0.001). More frequent hypoglycemic episodes in infants with NDM compared to older children with diabetes were seen by 63.2% of participants from high-incidence countries than from low-incidence countries (20%; p < 0.001) (Q31). Participants from high-incidence countries scored better results on knowledge about SU treatment than participants from low-incidence ones (p = 0.031) (Q33).

Experience of the Participants

Among the more experienced participants, 94.1% would start treatment with insulin, while 5.9% would choose SU. In contrast, among the less experienced participants, 77.5% would opt for insulin, and 20% would select SU (p = 0.03) (Q9). Short-acting insulin (82.4%) and regular insulin (14.7%) were preferred by the more experienced participants (less-experienced participants: short-acting insulin 52.5%, regular insulin 40.0%) (p = 0.004) (Q13). SU would be tried before sending genetic testing by 42.5% and 17.6% of less and more experienced participants, respectively (p = 0.005) (Q25). More-experienced participants scored better results concerning knowledge of insulin treatment in NDM (p = 0.011), short-term (p = 0.004) and long-term follow-up (p = 0.005), and more confidence in the management of NDM (p = 0.018) than less experienced participants (Q33); 1.5% of the former and 10% of the latter have never been involved in the management of NDM (p = 0.042) (Q41).

The K-ATP channel gene mutations were indicated as the most frequent cause of NDM by 72.5% of senior participants and 41.2% of junior participants (p = 0.014) (Q30). Senior participants scored better results about the knowledge of long-term follow-up (p = 0.045) and confidence in the management of NDM (p = 0.022) than junior ones (Q33).

Clinical Features

Participants from larger clinics would start the treatment with short-acting analogue (83.3%; regular insulin 16.7%), more frequently than participants from smaller clinics (61.7%; regular insulin 30.0%) (p = 0.021) (Q13) and would use CGMS more frequently (89.6%; smaller clinics 73.3%, p = 0.034) (Q16). At least five infants with NDM were followed up by 60.4% and 20% of participants from larger and smaller clinics, respectively (p < 0.001) (Q29). Eight of nine participants with more than 15 patients with NDM in follow-up worked in larger clinics. Participants from larger clinics scored higher results concerning knowledge of insulin treatment (p = 0.011), SU treatment (p = 0.039), short-term (p < 0.001) and long-term follow-up issues (p = 0.003), and confidence in the management of NDM (p = 0.013) (Q33). Finally, 45.8% of participants from larger clinics have guidelines in their unit for NDM (26.7% of participants from smaller clinics, p = 0.038) (Q36).

Participants who followed up at least five infants with NDM scored higher results concerning knowledge of diagnostic criteria (p = 0.022), genetics (p = 0.009), insulin treatment (p = 0.002), SU treatment (p = 0.008), short-long (p < 0.001) and long-term follow-up issues (p < 0.001) (Q33). Among participants who follow up with at least five patients, 51.2% have specific guidelines in their unit (vs. 25.4% of the other participants, p = 0.006) (Q36) and scored better results regarding confidence in the management of NDM (p = 0.01) (Q42).