Diagnostic Value of Laboratory Parameters for Distinguishing Between Herpes Zoster and Bacterial Superficial Skin and Soft Tissue Infections

Abstract

Clinical differentiation between superficial skin and soft tissue infections (SSTI, including cellulitis and erysipelas) and herpes zoster of the face can be difficult. Moreover, bacterial superinfection can develop in patients with herpes zoster. This may lead to delayed treatment or unnecessary use of antibiotics, which could lead to further microbial resistance or higher costs of treatment. This analysis of diagnostic parameters is often determined as standard of care in hospitalized patients and can help clinicians to guide their treatment decisions.Clinical differentiation between herpes zoster and bacterial superficial skin and soft tissue infections of the face can be difficult. In addition, diagnosis can be complicated by bacterial superinfection of lesional herpes zoster. The aim of this study was to determine whether inflammatory parameters, such as C-reactive protein (CRP) and blood counts, might be reliable biomarkers to distinguish between skin and soft tissue infections and herpes zoster when the face is infected. The study data (multivariate analysis and area under the curve) identified CRP (0.880) and leukocytes (0.730) together as the parameters that best discriminate between skin and soft tissue infections and herpes zoster. A CRP threshold ≥ 2.05 mg/dl indicated a diagnosis of skin and soft tissue infection with a sensitivity of 80% and specificity of 83.8%. For leukocytes ≥ 7.3×10 9 /l, diagnosis of skin and soft tissue infection had a sensitivity of 75% and specificity of 67.6%. Thus, when differential diagnosis is difficult, CRP and leukocytes should be determined, while parameters such as neutrophils or immature granulocytes do not add diagnostic value.

Disease duration and herpes zoster infection related to neutropenia in patients with systemic lupus erythematosus

“…A previous study compared clinical differences between 122 patients with superficial skin infection and 97 patients with herpes zoster infection. That study demonstrated that neutrophil counts were significantly lower in patients with herpes zoster infection than those with superficial skin infection (4.12 vs. 5.68 x10 9 /l; P<0.05) (13). Another study in adult patients with SLE reported that high glucocorticoid doses increased the risk of herpes zoster infection by 2% (P=0.03), whereas a study of children with SLE reported similar findings (14,15).…”

Herpes Zoster and Cardiovascular Disease: Exploring Associations and Preventive Measures through Vaccination

“…Distinguishing herpes zoster skin rashes from bacterial epidermal and facial soft tissue infections can be challenging in clinical practice. Moreover, bacterial superinfection of herpes zoster may complicate diagnoses [ 61 ]. When the differential diagnosis is difficult, C-reactive protein and leukocyte counts should be determined, whereas parameters such as neutrophils or immature granulocytes do not add diagnostic value.…”

S1 guideline: Differential diagnosis of acute and chronic redness of the lower legs

“…-CRP and white blood count are the best in vitro indications for skin and soft tissue infections as a differentiation from herpes zoster (CRP ≥ 2.05 mg/dl indicated erysipelas with a sensitivity of 80 % and a specificity of 83.8 %) [4,5].…”

“… –Initial fever, chills, and/or malaise occurring before or simultaneously with the erythema are practically always indicative of erysipelas (unpublished data). It is therefore essential to enquire about these symptoms specifically. –CRP and white blood count are the best in vitro indications for skin and soft tissue infections as a differentiation from herpes zoster (CRP ≥ 2.05 mg/dl indicated erysipelas with a sensitivity of 80 % and a specificity of 83.8 %) [4, 5]. –If trauma or surgery before occurrence of the erysipelas are reported, this may indicate phlegmon or type II necrotizing fasciitis according to Giuliani. –Differentiation from severe phlegmon: high fever, reduced general health, and lymph node swelling are indicative of severe phlegmon but may be absent in cases of initially limited phlegmon [6].…”