Utility of Serum Procalcitonin in Diagnosing Paroxysmal Sympathetic Hyperactivity in Patients with Traumatic Brain Injury

Background

Paroxysmal sympathetic hyperactivity (PSH) is a grave entity affecting patients following traumatic brain injury (TBI). It presents with cyclic and simultaneous fever, posturing, and other symptoms of sympathetic hyperactivity. Lack of diagnostic tests or biochemical markers and its propensity to mimic other common causes of fever in the neurotrauma intensive care unit (ICU) result in clinical dilemmas and management delay.

Case Descriptions

We present a case series of four patients (two adults and two pediatrics) with TBI who developed PSH during ICU stay. These patients presented with fever along with variable symptoms of sympathetic hyperactivity. However, the value of serum procalcitonin (PCT) was not elevated, and management of PSH was started. Serial monitoring of PCT helped in differentiating fever due to PSH from sepsis and thus the institution of appropriate and timely treatment of PSH and also helped to use antibiotics rationally.

Conclusion

The use of serum PCT in differentiating sepsis from systemic inflammatory reaction and its role in the initiation and titration of antibiotics are well described. PSH is a common entity after TBI, causing episodic fever and sympathetic hyperactivity, often confused with infectious pathology. Our report proposes the role of serum PCT in differentiating PSH from infectious etiology and management of two different clinical entities.

How to cite this article

Bindra A, Chowdhary V, Dube SK, Goyal K, Mathur P. Utility of Serum Procalcitonin in Diagnosing Paroxysmal Sympathetic Hyperactivity in Patients with Traumatic Brain Injury. Indian J Crit Care Med 2021;25(5):580–583.

ID: 135: SINGLE CELL GENE EXPRESSION STUDIES IN LUPUS MONOCYTES REVEAL A UNIQUE ANTII-INFLAMMATORY NON-CLASSICAL MONOCYTE POPULATION ASSOCIATED WITH CLINICAL QUIESCENCE

Background

Our previous studies have shown that different cell types from the same blood sample demonstrate diverse gene expression parameters. In follow up work, it seems that this diversity extends to cells of the same type from the same blood sample. In this study, we examine single cell gene expression in SLE patient monocytes and determine correlations with clinical features.

Methods

CD14++CD16− classical monocytes (CLs) and CD14dimCD16+ non-classical monocytes (NCLs) from SLE patients were purified by magnetic separation. The Fluidigm single cell capture and pre-amplification system was used for single cell capture and target gene pre-amplification. Fluidigm Biomark system (Rt-PCR system) was used to quantify expression of 87 monocyte-related genes. IFN-induced genes in monocytes were identified by culturing monocytes isolated from whole blood of healthy controls with or without IFN-α. Genes significant up-regulated by IFN were identified as IFN-induced genes in current study. An individual cell IFN score was given based upon the sum of expression of IFN-induced genes.

Results

Both CLs and NCLs demonstrated a wide range of expression of IFN-induced genes, and NCL monocytes had higher IFN scores than CL monocytes. Using unsupervised hierarchical clustering, we found four gene sets that clustered monocytes functionally. These included an IFN-induced gene set, two inflammatory gene sets, and one immunosuppressive gene set. Interestingly, we could define a large subset of NCL monocytes with upregulation of suppressive transcripts (including TGF-β and PDL1) and IFN-induced transcripts were also upregulated, while the two inflammatory gene sets were down-regulated. These cells were highly over-represented in a patient with inactive disease who was on immunosuppressants at the time of blood draw. The proportion of anti-inflammatory gene set expressing NCLs was inversely correlated with anti-dsDNA titers (rho=−0.77, p=0.0051) and positively correlated with C3 complement (rho=0.68, p=0.030) in the SLE patient group, suggesting that these cells are also associated with serological quiescence.

Conclusion

Using single cell gene expression, we have identified a unique population of NCL monocytes in SLE patients with upregulation of a combination of anti-inflammatory and IFN-induced transcripts. These cells correspond with clinical and serological quiescence.

Sweet's syndrome and Pneumocystis carinii pneumonia: two sequelae of low-dose cytosine arabinoside therapy in a patient with acute myeloid leukemia

Cytosine arabinoside in low dose is sometimes employed for treating acute myeloid leukaemia. We report here a case of acute myeloid leukemia, treated with low-dose cytosine arabinoside, who developed acute febrile neutrophilic dermatosis and Pneumocystis carinii pneumonia after attainment of remission. A direct effect of cytosine arabinoside on neutrophil function and an immunosuppressive potential in lower doses could be speculated.

Pyogenic meningitis: sonographic evaluation

Forty infants with proven pyogenic meningitis were evaluated by real time cranial sonography. A spectrum of sonographic abnormalities was observed which included echogenic sulci, focal or diffuse increase in parenchymal echoes, ventriculitis, ventriculomegaly with or without aqueductal block, subdural collection, parenchymal infarcts, abscess and subdural empyema. There were two infants with normal sonogram while encephalomalacia was seen in another two patients. An excellent correlation was observed between clinical profile, cerebrospinal fluid biochemistry and sonographic findings.