8
Diagnosis
Figure 1. General Approach for the Diagnosis of
Primary Immunodeficiency
1.3 EMERGENCY!
Immediate aggressive
evaluation and treatment
1.1 Suspected primary
immunodeficiency
YES
1.4 See Table 1
• Suspected combined defect or
syndrome– Figure 2
• Suspected antibody deficiency–
Table 3
• Suspected immune dysregulation–
Figure 3
• Suspected phagocyte defect–
Figure 4
• Suspected innate defect–
Figure 5
• Suspected autoinflammatory
syndrome– Figure 6
• Suspected complement deficiency–
Tables 9 and 10
• Suspected cytokine autoantibody–
Table 11 and SS 236-237
NO
1.2 Is SCID
possible?
1.5 If uncertain or insufficient
resources, consult or refer for
evaluation and/or treatment
• 1.1– The patient exhibits symptoms and signs consistent with a PIDD. It is assumed
that immunosuppressive therapy and other medical conditions potentially resulting
in secondary immunodeficiency and other anatomic or biochemical conditions
potentially predisposing to infection either have been excluded or are not
considered sufficient to explain the observed degree of infection susceptibility
(see SS 2).
• 1.2– Is the clinical presentation and initial laboratory evaluation consistent with
SCID (see SS 26)?
• 1.3– If the answer to 1.2 is yes, then the evaluation and management must be
expedited as much as possible. Patients with SCID are fragile and extremely
susceptible to infection. Early HSCT is associated with better outcomes, whereas
complications before HSCT indicate poorer prognosis.
• 1.4– If the answer to 1.2 is no, then another PIDD should be sought. The
characteristic clinical presentations of various categories of PIDDs are summarized
briefly in Table 1. Diagnostic information and algorithms for these categories are
presented in Figs 2 to 6; Tables 3, 9, 10, 11; and SSs 236 and 237.
• 1.5– If there is uncertainty or lack of resources for patient evaluation or care,
consultation with or referral to a provider with experience with PIDDs should
be undertaken. Although not stated explicitly in the figures that follow, this
consideration is implicit in the course of evaluation and treatment of all patients
with PIDDs (see SS 24).
