Differential diagnosis algorithm of endogenous catatonia, catatonia-morphic and catatonia-mimicking states

Subject relevance. The process of mental pathology pathomorphosis leads to the polymorphism of its clinical manifestations and, as a consequence – to difficulties in identification and differential diagnosis. The solution to this problem is in the adaption of diagnostic methodology to clinical realities by including into their structure instruments formed basing on pathomorphosis factors and trends. In this perspective, the most prominent example is endogenous catatonia, which in the academic tradition is conventionally affiliated with the form of schizophrenia with the same name. According to the classical understanding, endogenous catatonia, or, in the narrow sense – catatonic syndrome, is a group of intermittent motor disorders, arranged with polymorphic shell constellation of neuropsychiatric manifestations. The aim is to develop pathomorphosis adapted clinical algorithm of endogenous catatonia differential diagnostics. Materials and methods: 236 patients of Zaporizhzhia Regional Psychiatric Clinic were examined. Patients were divided into groups due to their mental disorders: Results. Using Bush-Francis Catatonia Rating scale as an instrument of clinical analysis and statistical research of results with A. Wald’s sequential analysis (modificated by E. V. Gubler) an algorithm of differential diagnostics of endogenus catatonia which includes 3 steps of Recognition Scale for Endogenous Catatonia is developed. Conclusion. Designed scales have a number of categorical differences from existing analogues, foremost by virtue of specificity of clinical-discursion compositions of


Subject relevance
The process of mental pathology pathomorphosis (PM) leads to polymorphism of its clinical manifestations and, as a consequence -to difficulties in identification and differential diagnosis. The solution to this problem is in the adaption of diagnostic methodology to clinical realities by including into their structure instruments formed basing on PM factors and trends [18][19][20][21][22].
In this perspective, the most prominent example is endogenous catatonia (EC), which in the academic tradition conventionally is affiliated with the form of schizophrenia with the same name. According to the classical understanding, EC, or, in the narrow sense -catatonic syndrome (CS), is a group of intermittent motor disorders, arranged with polymorphic shell constellation of neuropsychiatric manifestations [1,2,[19][20][21][22].
With psychiatric diagnosis formalization degree incensement, as a result of adaptation to the requirements of evidence-based medicine, which is typical of the international psychiatric discourse of XXI century, diagnostic algorithms that provide specialized diagnostic scales have been established in clinical practice, including: Rosebush and colleagues scale (1999), The Modified Rogers Scale (MRS, 1991), Bush-Francis Catatonia Rating Scale (BFCRS, 1996), Northoff Catatonia Scale (NCS, 1999), Catatonia Rating Scale (CRS, 2008). Analysis of scales above finds lack of signs that are specific to EC structure, contamination of diagnostic positions and replication of same phenomena. That leads to discursive heterogeneity and artificial etiopatogenetic homogenization, without any formal system of adaptation to EC PM [3][4][5][6][7][8][9][10][11][12][13][14][15].
In this regard, the development of PM adapted diagnostic tool for EC differentiation is an urgent task of modern clinical psychiatry.
The aim of this study is to develop pathomorphosis adapted clinical algorithm of endogenous catatonia differential diagnostics.
The research design and basic features of contingents and methods 453 patients struggling catatonia and behavior disorders of different genesis have been examined on the basis of the Zaporizhzhia Regional Psychiatric Clinic. For further examination 236 patients were chosen by prevailing criteria (primarily by the nosology). All the patients have been hospitalized in stable somatic state due to psycho-somatic examination. The duration of the disorder takes from 5 to 30 years. The average age of patient was approximately 34 years.
Patients were divided into groups due to their mental disorders: -core group: patients with elements of endogenous catatonia in the structure of different clinical form of schizophrenia (there are 144 patients in this group); -comparison group # 1: 69 patients with late neurotropic effects of neuroleptic therapy (LNENT); -comparison group # 2: 103 patients with catatonomorphic dissociative disorders (CDD); On the stage of testing diagnostic tool sensitivity and specificity, 30 patients with schizophrenia disorder with excluded phenomena of catatonic range were included to the comparison group.
Following research methods were used: -psycho-pathological method -used for identification of disorder due to ICD-10 and analysis of its course with the help of the diagnostic scales (PANSS / Bush-Francis Catatonia Rating Scale (G. Bush, M. Fink, G. Petrides, 1996) [16,17]; -catamnestic method -analysis of new diagnostic specificity, determine the effectiveness of the developed differential diagnostics tool.
-clinical and statistical methods -were used for research results processing and assessment of the results'
With DC and IM calculations by the formulas (E. V. Gubler, 1978); where: DC -diagnostic coefficient; IM -Kullback's informativeness measure; А1 -sign frequency in comparison group # 1; А2 -sign frequency in comparison group # 2. All important signs were made into differential-diagnostic tables (step 1, 2 and 3 ECDS) and posted in descending order of informativeness: Filling scales of clinical forms was based on consistent observation and registration of psychopathological phenomena, postural and facial features, articulation, content, emphatic intonational-verbal communication parameters, neurological stigmas and complex patterns of behavior.
"Yes" mark was put in table in case of the phenomena presence, "No" mark was put in table in case of phenomena absence. On filling each line, the amount calculation of DC has been produced. By dint of mark DC addition, reaching value of ∑ DC = +13 or -13, imposed preliminary diagnostic  conclusion of belonging psychopathological disorders to LNENT, CDD and OrCD (if ∑ DC = +13), or to primary (endogenous) catatonia (if ∑ DC = -13), which has confidence level = 95 % (p = 0.05). Reaching value of ∑ DC = + 20 or -20 imposed a final diagnostic conclusion, which has confidence level = 99 % (p = 0.01). If higher confidence level is needed, process of phenomena education continues until reaching value ∑ DC = +30 or -30 appropriate = 99.9 % (p = 0.001) confidence level.
There is a protocol of differential diagnostic of EC based on ECDS, steps 1-3 (Fig. 1).
The analysis of the developed protocol of differential diagnosis has been performed. Taking into account specificity of views on the discuss on the identification of psychomotorical and behavioral disorders of catatonic range double check in 2 vectors of the sensitivity and specificity of new diagnostics tool was made on anonymized and randomized contingent (sensitivity analysis) and on 30 patients of psychiatric hospital excepted catatonic semiotics (specificity analysis). These 2 vectors are:

Conclusions:
1. There differential diagnostic properties of clinical-psychopathological semiotics signs were revealed and analyzed in EC, LNENT, CDD and OrCD patients. Values of DC and IM were calculated. Reliability analysis of differences and IM values allowed separating valid signs for syndromic accessory of catatonia differential.
2. All important signs were made into differential-diagnostic tables and posted in descending order of informativeness ∑ IM. All the valid and discursively-native marks were used in based on three-step realization algorithm ECDS protocol. Designed scale allows making a diag-  nostic decision of relatively psychopathological disorder to EC, LNENT, CDD or OrCD on any reliability level: 95 % (p = 0.05), 99 % (p = 0.01) or 99.9 % (p = 0.001). Based on the designed scale EC differential diagnostic protocol has been formed. Using of designed protocol allowed reaching the level of true positive results (sensibility) = 94.43 %, pseudo-negative = 5.56 %, true negative (specificity) = 90.00 %, pseudo-positive = 10.00 %.
Designed scales have a number of categorical differences from existing analogues, foremost by virtue of specificity of clinical-discursion compositions of using marks and disqualified conditions and excluding phenomena spectrum availability.