Summary

ASH 2019 guidelines provide 21 evidence-based recommendations for managing adults and children with newly diagnosed, persistent, and chronic ITP with non–life-threatening bleeding. Management options addressed include observation, corticosteroids, IVIG, anti-D immunoglobulin, rituximab, splenectomy, and TPO-RAs. Compared with the 2011 guideline, the update favors shorter corticosteroid courses, emphasizes shared decision-making for second-line therapy, and incorporates TPO-RAs as a preferred second-line option in both adults and children. The guideline does not cover diagnosis, life-threatening bleeding, pregnancy, or agents introduced after 2017.

Key Recommendations

In adults with newly diagnosed ITP and platelet count <30 ×10⁹/L who are asymptomatic or have minor mucocutaneous bleeding, treat with corticosteroids rather than observe.
In adults with newly diagnosed ITP and platelet count ≥30 ×10⁹/L who are asymptomatic or have minor mucocutaneous bleeding, observe rather than treat with corticosteroids (strong recommendation).
Use a short course (≤6 weeks including taper) of prednisone rather than a prolonged course (>6 weeks) for initial therapy in adults (strong recommendation).
Either prednisone (0.5–2 mg/kg/day) or dexamethasone (40 mg/day × 4 days) is acceptable for initial corticosteroid therapy in adults; dexamethasone may give faster 7-day response.
Use corticosteroids alone rather than rituximab plus corticosteroids for initial therapy of newly diagnosed adult ITP.
Admit adults with newly diagnosed ITP and platelet count <20 ×10⁹/L; manage established adult ITP with platelet count <20 ×10⁹/L as outpatient.
For adults with ITP ≥3 months who are corticosteroid-dependent or unresponsive, suggest TPO-RA over rituximab and TPO-RA or rituximab over splenectomy; delay splenectomy ≥1 year after diagnosis when possible.
Either eltrombopag or romiplostim is acceptable as the TPO-RA in adults; choice depends on patient preference for oral daily vs weekly subcutaneous administration.
In children with newly diagnosed ITP and no/mild bleeding, manage as outpatient regardless of platelet count, and observe rather than treat with corticosteroids, IVIG, or anti-D (strong recommendations against IVIG and anti-D when only skin manifestations).
In children with newly diagnosed ITP and non–life-threatening mucosal bleeding/diminished HRQoL, use corticosteroids ≤7 days (strong); prefer prednisone 2–4 mg/kg/day (max 120 mg) × 5–7 days over dexamethasone, and corticosteroids over IVIG or anti-D.
In children unresponsive to first-line therapy, suggest TPO-RAs over rituximab or splenectomy, and rituximab over splenectomy.
Ensure appropriate immunizations and antibiotic prophylaxis counseling prior to splenectomy; ensure hematology follow-up within 24–72 hours of diagnosis or relapse.
Monitor patients on corticosteroids for hypertension, hyperglycemia, sleep/mood disturbances, GI ulceration, glaucoma, myopathy, osteoporosis, and assess HRQoL.

Thresholds & Doses

Adult observation threshold: platelet count ≥30 ×10⁹/L (asymptomatic/minor bleeding) — observe rather than treat.
Adult corticosteroid treatment threshold: platelet count <30 ×10⁹/L — treat.
Adult inpatient admission threshold (newly diagnosed): platelet count <20 ×10⁹/L.
Adult corticosteroid course duration: ≤6 weeks (including taper); avoid >6 weeks.
Adult prednisone dose: 0.5–2 mg/kg/day.
Adult dexamethasone dose: 40 mg/day × 4 days.
Pediatric corticosteroid course duration: ≤7 days; avoid >7 days.
Pediatric prednisone dose: 2–4 mg/kg/day, maximum 120 mg/day, for 5–7 days.
Pediatric dexamethasone dose: 0.6 mg/kg/day, maximum 40 mg/day × 4 days.
Elderly threshold for considering corticosteroids despite higher platelet count: >60 years.
Delay splenectomy ≥12 months after diagnosis when possible (potential spontaneous remission).
Definitions: newly diagnosed ITP <3 months; persistent 3–12 months; chronic >12 months; remission platelet >100 ×10⁹/L at 12 months.
Corticosteroid-dependent: ongoing need for prednisone >5 mg/day or frequent courses to maintain platelets ≥30 ×10⁹/L.
Response definitions: early (≥30 ×10⁹/L and doubling at 1 week); initial (at 1 month); durable (at 6 months).
ICH incidence: 1.4% adults, 0.1–0.4% children; severe bleeding 9.5% adults, 20.2% children.

Citations

Recommendations 1a–1b — corticosteroids vs observation thresholds in adults
Recommendations 2a–2b — inpatient vs outpatient management thresholds in adults
Recommendation 3 — short (≤6 weeks) vs prolonged corticosteroid course in adults
Recommendation 4 — prednisone vs dexamethasone dosing in adults
Recommendation 5 — corticosteroids alone vs rituximab + corticosteroids initial therapy
Recommendations 6–9 and Figure 1 — second-line therapy algorithm (TPO-RA, rituximab, splenectomy)
Recommendations 10–13 — outpatient management and observation in children with newly diagnosed ITP
Recommendations 14–18 — corticosteroid duration/type and choice among IVIG, anti-D, corticosteroids in children with mucosal bleeding
Recommendations 19–21 — second-line therapy in children (TPO-RA preferred over rituximab and splenectomy)
Table 3 — definitions of ITP phases, response criteria, and corticosteroid dependence