Nurdan Köktürk, Asiye Kanbay, Neslihan Bukan , Numan EkimGazi University School of Medicine

The Diagnostic Value of Serum

Procalcitonin In Differential Diagnosis

of Pulmonary Embolism and

Community Acquired Pneumonia

Introduction 1

Fever occurs in 26% of pulmonary embolism (PE) patients

Presence of high fever may cause confusion in differential diagnosis of PE vs. pneumonia

Introduction 2

Serum procalcitonin (PCT) level is a useful test to identify bacterial infections

PCT is a prohormone of the calcitonin that is produced by the C cells of the thyroid gland

It is secreted as part of systemic inflammatory response to infection

Serum values of PCT correlated with the type and severity of infection

Aim

To investigate the diagnostic value of PCT in differential diagnosis of PE and community acquired pneumonia (CAP)

The second goal is to demonstrate possible relation of PCT with other systemic markers in appropriately treated patients

Study group Group 1: PE with fever in first 72 hours (n=8) Group 2: PE without fever (n=16) Group 3: Community acquired pneumonia (n=22)

Patients were evaluated at the initial diagnosis and the 3rd day of the treatment of the hospitalization days.

Blood leukocyte count, CRP, ESR, PCT, IL6 and TNF α levels were measured at defined measurement points.

Group analysis was performed to see how those parameters were influenced by appropriate treatment.

Materials and Method

89 patients with PE

65 patient excludedpatients using antibacterial agent (n=17)lung cancer (n=3), urinary tract infection (n=19)wound infection (n=4),lower respiratory tract infection (n=13)extensive surgery (n=7)early major trauma (n=1)

22 patients with CAP

113 patients were eligible

8 PE patients with fever16 patients without fever

Table1: Comparison of values at initial evaluation in three groups

ParameterGroup 1

PE with feverGroup 2

PE without feverGroup 3

CAPP value

Body temperature (0C)

38.17±0.48 36.58±0.22 38.42±0.79 0.000

Leukocyte count /mm3

10737.50±2426.01

10340.62±3795.40

12170±5853.50

0.611

CRP level (mg/dl) 78.25±72.25 41.56±37.88 127.04±67.69 0.002

ESR (mm/hr) 93.87±19.26 44.18±21.62 76.27±33.09 0.001

Procalcitonin (ng/ml) 0.48±0.77 0.14±0.17 2.24±0.99 0.000

TNF α (pg/ml) 30.92±20.47 55.65±80.38 56.12±80.44 0.825

IL6 (pg/ml) 165.75±196.53 101.09±138.12 283.82±294.78

0.018

Temp (0C) Leukocyte (/mm3) CRP (mg/dl ) ESR (mm/hr ) Procalcitonin( ng/ml)

TNF alpha( pg/ml)

IL6 (pg/ml )

Group 1 (1.day)38.17±0.48

* 10737. 50±2426* 78.25±72.25* 93.87±19.26* 0.48±0.77 30.92±20.47 165.75±196.53*

Group 1 (3.day) 37.32±0.29 5620±1222.91 68.37±66.10 51.25±20.95 0.25±0.37 18.29±35.13 78.63±165.37

Group 2 (1.day) 36.58±0.22 10340.62±3795.43* 41.56±37.88* 44.18±21.62* 0.14±0.17 55.65±80.38* 101.09±138.12*

Group 2 (3.day) 36.43±0.22 6864.37±1339.58 21.22±22.93 22.68±15.81 0.12±0.14 16.03±17.28 27.8±50.80

Group 3 (1.day)38.42±0.79

* 12170±5853.50* 127.04±67.69* 76.27±33.09* 2.24±0.99* 56.12±80.44* 283.82±294.78*

Group 3 (3.day) 37.34±0.78 7880.45±2666.85 74.72±47.94 40.77±22.71 0.92±0.62 32.96±75.25 83.45±152.10

Table 2: Initial and third day‘s laboratory measurements

*:Shows statistically difference

The correlation of serum PCT level and leukocyte, sedimentation levels was not reach statistical significance.

The correlation reached statistical significance between serum PCT level and CRP, body temperature (r=0.455, p=0.001; r=0.653, p=0.000; respectively).

Discussion 1:

Patients with CAP had significantly higher PCT levels

than PE patients with or without fever on admission.

PCT levels did not change with anticoagulant

treatment in both PE groups, in CAP group antibiotic

therapy caused the decreasing level of PCT.

PE patients did not show PCT positivity in PE group even febrile patients Sedimentation rate, CRP and blood leukocyte counts are reached statistical difference by

anticoagulant and antibacterial therapy in all groups.

Isabelle D, Marc A,Olivier A, et al. Procalcitonin Measurement for Differential Diagnosis Between Pulmonary Embolism and Pneumonia, Crit Care Med, 31 (2) 661, 2003.

Discussion 2

Discussion 3

PCT was identified as a better discriminating marker than CRP to characterize the level of inflammation according to the ACCP/SCCMConsensus Conference criteria. It is more specific to inflammation caused by infection than CRP.

CRP is affected from immunosuppressive treatment (ie; steroids) but PCT levels do not change under those medications.

Another superiority of PCT to CRP is, it is rapidly increases in infectious conditions

Discussion 4

ProRESP study group: 200 patients

PCT guided antibiotic therapy: the percentage of patients in the PCT group, antibiotic therapy was reduced by almost 50%, as compared with standard group.

Christ-Crain M, Jaccard-Stolz D, Bingisser R, et-al. Effect of procalcitonin-guided treatment on antibiotic use and outcome in lower respiratory tract infections: cluster-randomised, single blinded intervention trial. Lancet 2004:363:600-6007.

Conclusion

These findings suggested that serum PCT levels might be more useful than blood leukocyte count, CRP, and ESR to differentiate especially PE with fever from CAP.