The effect of myotonic dystrophy type 1 on temporomandibular joint and dentofacial morphology: A CBCT analysis.

BACKGROUND: Myotonic dystrophy type 1 (DM1) is a neuromuscular multisystem disease. Early involvement of facial muscles may produce an extra load on the temporomandibular joint (TMJ) in DM1. OBJECTIVES: This study aimed to investigate the morphological analyses of the bone components of temporomandibular joint (TMJ), and dentofacial morphology in myotonic dystrophy type 1 (DM1) patients by cone-beam computed tomography (CBCT). METHODS: Sixty-six individuals (33 DM1, and 33 healthy subjects) age ranging from 20 to 69 were included in the study. Clinical examinations of the patients' TMJ regions and evaluation of dentofacial morphology (maxillary deficiency, open-bite, deep palate and cross-bite) were performed. Dental occlusion was determined based on Angle's classification. CBCT images were evaluated regarding mandibular condyle morphology (convex, angled, flat and round) and osseous changes observed in the condyle (normal, osteophyte, erosion, flattening, sclerosis). DM1-specific morphological and bony TMJ alterations were determined. RESULTS: DM1 patients showed a high prevalence of morphological and osseous TMJ changes, and statistically significant skeletal alterations. The analysis of CBCT scans indicated the prevalent condylar shape among patients with DM1 was flat, the main osseous abnormality was flattening, there was a tendency towards skeletal Class II and a posterior cross-bite was frequently detected in DM1 patients. There was no statistically significant difference between the genders on the parameters evaluated in both groups. CONCLUSION: Adult patients with DM1 presented a high frequency of crossbite, tendency to skeletal Class II and morphological osseous alterations of TMJ. The analysis of the morphological condylar alterations in patients with DM1 may be beneficial in the diagnosis of TMJ disorders. This study reveals DM1-specific morphological and osseous TMJ alterations to provide an appropriate orthodontic/orthognathic treatment planning to patients.

Neurological comorbidities and novel mutations in Turkish cases with neurofibromatosis type 1.

Background and purpose:

Neuro­fibromatosis type 1 (NF1) is a rare, auto­somal dominant multisystemic disease. The NF1 gene is localized on chromosome 17q11.2. Patients with NF1 have different clinical presentations and comorbidities. The aim of the present study is to determine the novel mutations and neurological comorbidities of NF1.

Patients who were diagnosed with NF1 by clinical criteria of the National Institutes of Health were included in the study. After a detailed examination, the NF1 gene was analysed with the help of next generation sequencing technology from pe­ripheral blood samples via MiSeq (Illu­mina, USA). Bioinformatic analyzes were per­for­med to evaluate the clinical sig­ni­fi­cance of the detected variants via the in­ternational databanks in accordance with the ACMG (American College of Medical Ge­netics) guide­line. In addition, cerebral-spinal MRI, cerebral angiography, and ENMG exa­mi­na­tions were performed if deemed necessary.

Twenty patients (12 female, 8 male) were included in the study. The mean age was 25.8±10 (10-56) years. Previously defined 13 different pathogenic mutations according to the ACMG criteria were identified in 18 patients. Also, two novel mutations were detected in 2 cases. Moreover, neurological comorbidities (moyamoya disease, multiple sclerosis, Charcot Marie Tooth Type 1A) were found in 3 patients with NF1.

In the present study two novel mutations and three different neurological comorbidities were identified in NF1.

The Impact of the COVID-19 Lockdown on the Quality of Life in Chronic Neurological Diseases: The Results of a COVQoL-CND Study.

BACKGROUND: Coronavirus disease 2019 (COVID-19) pandemic and lockdown period may induce an impairment in quality of life (QoL), disruption in treatment (DIT), and posttraumatic stress disorder (PTSD) in chronic neurological diseases (CNDs). To reach this information, a multicenter, cross-sectional study (COVQoL-CND) was planned. Parkinson's disease (PD), headache (HA), multiple sclerosis (MS), epilepsy (EP), polyneuropathy (PNP), and cerebrovascular disease (CVD) were selected as the CND. METHODS: The COVQoL-CND study includes demographic data, the World Health Organization Quality of Life short form (WHOQOL-BREF), and Impact of Event Scale-Revised (IES-R) forms. RESULTS: The mean age of a total of 577 patients was 49 ± 17 (19-87 years), and the ratio of female/male was 352/225. The mean age of patients with PD, HA, MS, EP, PNP, and CVD were 65 ± 11, 39 ± 12, 38 ± 10, 47 ± 17, 61 ± 12, and 60 ± 15 years, respectively. The IES-R scores were found to be higher in the younger group, those with comorbid disease, contacted with CO-VID-19 patients, or diagnosed with COVID-19. In the group with a high IES-R score, the rate of DIT was found to be high. IES-R scores were negatively correlated with QoL. IES-R total scores were found highest in the CVD group and lowest in the PD group. The ratio of DIT was found highest in the PNP group and the lowest in the EP group. Contact with CO-VID-19 patients was high in the EP and HA group. CONCLUSIONS: The results of the COVQoL-CND study showed that lockdown causes posttraumatic stress and deterioration in the QoL in CND.

The importance of heart rate variability in predicting cardiac autonomic dysfunction in patients with amyotrophic lateral sclerosis.

AIM: Amyotrophic lateral sclerosis (ALS) is a progressive disease characterized by degeneration in the upper and lower motor neurons of the corticospinal tract, brain stem, and spinal cord. Recent studies have revealed that the disease does not present solely with motor neuron involvement. Accordingly, the aim of this study is to investigate the presence of cardiac autonomic impairment in patients diagnosed with ALS. MATERIAL AND METHOD: A total of 61 patients, who were diagnosed with ALS according to the Revised El Escorial Criteria (R-EEC), were included in this prospective study, in addition to the 29 healthy individuals, who were included in the study as controls. In order to assess the cardiac autonomic involvement, the presence of orthostatic hypotension was investigated, and transthoracic echocardiography and 24-hour electrocardiogram (ECG) using a Holter monitor were performed. RESULTS: Orthostatic hypotension was detected in 14 (22.2%) patients. Holter electrocardiogram results of the patient group revealed statistically significantly lower heart rate variability (HRV) indicators in the time domain (SDNN, SDANN, SDNN index, rMSSD, and pNN50) and in the frequency domain (high frequency [HF], low frequency [LF], and very low frequency [VLF]) than those of the control group (P < .05). CONCLUSION: Contrary to the popular opinion, cardiac autonomic dysfunction in patients with ALS can occur at any stage of the disease. Therefore, it is recommended that the patients are evaluated via periodic examinations during the follow-up period for cardiac autonomic involvement.

Three-dimensional assessment of pharyngeal airway in individuals with myotonic dystrophy type 1

Background/aim: The objectives of this study were to assess pharyngeal airway volume (PAV) in patients with myotonic dystrophy type 1 (DM1) by cone-beam computerized tomography (CBCT) and to evaluate the impact of diaphragm thickness and pulmonary function tests on PAV. Materials and methods: Thirty DM1 patients (10 female and 20 male; mean age 42.40 ± 12.07) were included in the study. Age and sex-matched thirty patients were participated as control group. In DM1 group pulmonary function tests (PFT) were performed. Independent t-test was used to compare PAV values of patients with DM1 and control group. The Mann­Whitney U test was used to compare the parameters according to sex ( p < 0.05). Pearson and Spearman correlation tests were used to evaluate the relationships between parameters of DM1 patients (p < 0.05). A multiple linear regression analysis was performed to explain the PAV with parameters that showed positive correlation with PAV. Results: Age of onset and disease duration were 22.37 ± 8.45 and 20.03 ± 12.08, respectively, in patients with DM1. PAV values of control group were significantly lower than DM1 group ( p < 0.001). Forced expiratory volume in 1 s and forced volume vital capacity values were higher in males than females in DM1 group according to sex ( p < 0.001). PAV values were greater in male patients than females of the DM1 group ( p = 0.022). Diaphragm thickness in DM1 group after inspiration and expiration were 2.60 ± 0.65 and 1.94 ± 0.40, respectively. According to the regression analysis, DTai and FVC were significantly explained the PAV. Conclusion: PAV was higher in DM1 group. There was a significant positive correlation between diaphragm thickness, pulmonary functions, and PAVs of DM1 patients. The amount of the PAV was mostly influenced by DTai and FVC. It is recommended to evaluate the PAV in patients with DM1 because of impaired respiratory functions and pharyngeal muscle involvement.

Revisiting the complex architecture of ALS in Turkey: Expanding genotypes, shared phenotypes, molecular networks, and a public variant database.

The last decade has proven that amyotrophic lateral sclerosis (ALS) is clinically and genetically heterogeneous, and that the genetic component in sporadic cases might be stronger than expected. This study investigates 1,200 patients to revisit ALS in the ethnically heterogeneous yet inbred Turkish population. Familial ALS (fALS) accounts for 20% of our cases. The rates of consanguinity are 30% in fALS and 23% in sporadic ALS (sALS). Major ALS genes explained the disease cause in only 35% of fALS, as compared with ~70% in Europe and North America. Whole exome sequencing resulted in a discovery rate of 42% (53/127). Whole genome analyses in 623 sALS cases and 142 population controls, sequenced within Project MinE, revealed well-established fALS gene variants, solidifying the concept of incomplete penetrance in ALS. Genome-wide association studies (GWAS) with whole genome sequencing data did not indicate a new risk locus. Coupling GWAS with a coexpression network of disease-associated candidates, points to a significant enrichment for cell cycle- and division-related genes. Within this network, literature text-mining highlights DECR1, ATL1, HDAC2, GEMIN4, and HNRNPA3 as important genes. Finally, information on ALS-related gene variants in the Turkish cohort sequenced within Project MinE was compiled in the GeNDAL variant browser (www.gendal.org).

Antioxidant imbalance in the erythrocytes of Myotonic dystrophy Type 1 patients.

The most common form of muscular dystrophy is known as Myotonic dystrophy Type 1 (DM1) in adults. It was aimed to investigate the relationship between antioxidant imbalance and diaphragm thickness with pulmonary function test results in peripheral blood of Myotonic Dystrophy Type 1 patients. In the prospective study, 33 DM1 and 32 healthy control groups were taken after the ethics committee decision (2018-10529). Antioxidant defence system enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), glutathione S-transferase (GST) and thiobarbituric acid reactive species (TBARS) levels were studied in blood samples. Also, muscular strength (MRC score), creatine kinase (CK) and diaphragm thicknesses were measured, and pulmonary function tests were performed. Among the studied parameters, TBARS levels and GPX, GR and GST activities in erythrocytes of DM1 patients showed a significant decrease in the range of 29-45% compared to the control group. MRC score, diaphragm thickness and inspiratory function test results at the end of inspiration and expiration were found lower though CK levels were higher in DM1 group. In the patient group, a positive correlation was found between antioxidant parameters (TBARS, CAT and GST) with diaphragm thicknesses and pulmonary function test though GPX showed a negative correlation with them. It was emphasized that the data obtained shows the harmful/pathogenic role of oxidative stress caused by free radicals in DM1, and also provide useful data for the treatment and processes of this disease.

Quality of life and related factors among chronic hepatitis B-infected patients: a multi-center study, Turkey.

BACKGROUND: The aim of this study was to assess health-related quality of life (HRQOL) among chronic hepatitis B (CHB) patients in Turkey and to study related factors. METHODS: This multicenter study was carried out between January 01 and April 15, 2015 in Turkey in 57 centers. Adults were enrolled and studied in three groups. Group 1: Inactive HBsAg carriers, Group 2: CHB patients receiving antiviral therapy, Group 3: CHB patients who were neither receiving antiviral therapy nor were inactive HBsAg carriers. Study data was collected by face-to-face interviews using a standardized questionnaire, Short Form-36 (SF-36) and Hepatitis B Quality of Life (HBQOL). Values equivalent to p < 0.05 in analyses were accepted as statistically significant. RESULTS: Four thousand two hundred fifty-seven patients with CHB were included in the study. Two thousand five hundred fifty-nine (60.1 %) of the patients were males. Groups 1, 2 and 3, consisted of 1529 (35.9 %), 1721 (40.4 %) and 1007 (23.7 %) patients, respectively. The highest value of HRQOL was found in inactive HBsAg carriers. We found that total HBQOL score increased when antiviral treatment was used. However, HRQOL of CHB patients varied according to their socio-demographic properties. Regarding total HBQOL score, a higher significant level of HRQOL was determined in inactive HBV patients when matched controls with the associated factors were provided. CONCLUSIONS: The HRQOL score of CHB patients was higher than expected and it can be worsen when the disease becomes active. Use of an antiviral therapy can contribute to increasing HRQOL of patients.

The effects of valproic acid and carbamazepine on strength-duration properties of peripheral nerve.

OBJECTIVE: To study strength-duration properties of motor and sensory axons to evaluate whether there is a change in current through the persistent sodium (Na+) channels of sensory and motor axons in peripheral nerves of epileptic patients before and after valproic acid (VPA) and carbamazepine (CBZ) treatment due to the presence of similar channels in the CNS and peripheral nervous system (PNS). METHODS: This study, conducted in Baskent University Faculty of Medicine, Adana, Turkey from January 2011 to February 2012, involved 10 patients with partial epilepsy, 10 patients with primary generalized epilepsy who were not currently prescribed anticonvulsant therapy, and 10 control subjects. Using an electromyography machine, stimulus intensity was performed to produce the target (40% of maximum) compound muscle action potentials and compound sensory action potentials. The currents required for different stimulus durations, 0.05, 0.1, 0.2, 0.3, 0.5, and 1 ms, were produced. Stimulus-response curves were then constructed, and the strength-duration time constants were estimated using Weiss`s formula. RESULTS: The rheobase of motor and sensory fibres was lower in the control group than the values of patients before and after CBZ and VPA therapy. CONCLUSIONS: In the PNS of epileptic patients, CBZ and VPA therapy results in decreased axonal excitability. This method may be used in investigating the underlying pathology of peripheral nerve diseases in vivo.

Heart rate recovery in epilepsy.

Autonomic manifestations regarding cardiac function in epilepsy are not rare and are being recognized with increasing frequency. The aim of this study was to assess autonomic function by measuring heart rate recovery (HRR), an index of vagal activity, in patients with epilepsy who were not taking any medication. Fourteen patients (eight with primary generalized epilepsy, four with secondary generalized epilepsy, and two with complex partial epilepsy) and 14 control subjects underwent exercise tolerance tests according to the modified Bruce protocol. HRR at 1 and 3 min (HRR1 and HRR3) were calculated. HRR1 and HRR3 were increased in patients with epilepsy. These results suggest increased parasympathetic function in epilepsy and support results of previous studies indicating autonomic dysfunction in epilepsy.

Evaluation of ALSFRS-R Scale with Fuzzy Method in Amyotrophic Lateral Sclerosis.

Introduction: Amyotrophic lateral sclerosis (ALS) is a disease with high morbidity and mortality that adversely affects the activities of daily living. Disease progression in ALS is characterized by loss of function in bulbar, motor, and respiratory parameters. The revised amyotrophic lateral sclerosis functional rating scale (ALSFRS-R), which consists of 12 criteria, is used to determine disease effects on each of these functions. While each criterion is equally important when calculating the total ALSFRS-R score, the importance levels of the 12 criteria may vary in clinical practice. In this classical approach, the relationships among the parameters are not considered and the effects of bulbar, spinal, and respiratory dysfunctions on a patient's activities of daily living may be different. Methods: In this study, we aimed to evaluate ALS cases with the ALSFRS-R fuzzy method. Although each subheading in the ALSFRS-R had the same score, the disease score was determined by the fuzzy ALSFRS-R method, based on whether a subheading had priority in management of the disease. While creating the functional rating scale ALSFRS-R approach, fuzzy ALSFRS-R score values were obtained by creating fuzzy models for each main group and integrating the fuzzy model results of each main group into a separate model. Results: In total, 50 patients with definite ALS according to the El Escorial criteria (33 men [66%] and 17 women [34%]; mean age, 58.49±10.01 years) were included in the study. When ALSFRS-R results and fuzzy ALSFRS-R results were compared, the prioritization order of 45 patients increased using the fuzzy ALSFRS-R score, while the prioritization order of five patients remained the same in both evaluations. Conclusion: The approach obtained by using fuzzy membership functions and decision rules, formed in accordance with expert opinion, was applied to the data of 50 patients from a large-scale hospital. In total, 90% of the patients had increased prioritization when using the fuzzy ALSFRS-R scoring method. Our results showed that the fuzzy approach provided more accurate information regarding a patient's condition.

Improved Kidney Allograft Function after Early Conversion of Fast IR-Tac Metabolizers to LCP-Tac.

Fast tacrolimus (Tac) metabolism is associated with a more rapid decline of renal function after renal transplantation (RTx). Because the pharmacokinetics of LCP-Tac (LCPT) and immediate-release Tac (IR-Tac) differ, we hypothesized that switching from IR-Tac to LCPT in kidney transplant recipients would improve the estimated glomerular filtration rate (eGFR), particularly in fast metabolizers. For proof of concept, we performed a pilot study including RTx patients who received de novo immunosuppression with IR-Tac. A Tac concentration-to-dose ratio (C/D ratio) < 1.05 ng/mL·1/mg defined fast metabolizers and ≥1.05 ng/mL·1/mg slow metabolizers one month after RTx. Patients were switched to LCPT ≥ 1 month after transplantation and followed for 3 years. Fast metabolizers (n = 58) were switched to LCPT earlier than slow metabolizers (n = 22) after RTx (2.0 (1.0−253.1) vs. 13.2 (1.2−172.8) months, p = 0.005). Twelve months after the conversion to LCPT, Tac doses were reduced by about 65% in both groups. The C/D ratios at 12 months had increased from 0.66 (0.24−2.10) to 1.74 (0.42−5.43) in fast and from 1.15 (0.32−3.60) to 2.75 (1.08−5.90) in slow metabolizers. Fast metabolizers showed noticeable recovery of mean eGFR already one month after the conversion (48.5 ± 17.6 vs. 41.5 ± 17.0 mL/min/1.73 m², p = 0.032) and at all subsequent time points, whereas the eGFR in slow metabolizers remained stable. Switching to LCPT increased Tac bioavailability, C/D ratio, and was associated with a noticeable recovery of renal function in fast metabolizers. Conversion to LCPT is safe and beneficial early after RTx.

Neuropathic Pain Frequency in Neurology Outpatients: A Multicenter Study.

INTRODUCTION: Neuropathic pain is common, but the frequency of misdiagnosis and irrational treatment is high. The aim of this study is to evaluate the rate of neuropathic pain in neurology outpatient clinics by using valid and reliable scales and review the treatments of patients. METHODS: The study was conducted for 3 months in eleven tertiary health care facilities. All outpatients were asked about neuropathic pain symptoms. Patients with previous neuropathic pain diagnosis or who have neuropathic pain symptoms were included and asked to fill painDETECT and douleur neuropathic en 4 questions (DN4) questionnaire. Patients whose DN4 score is higher than 3 and/or painDETECT score higher than 13 and/or who are on drugs for neuropathic pain were considered patients with neuropathic pain. The frequency of neuropathic pain was calculated and the treatments of patients with neuropathic pain were recorded. RESULTS: Neuropathic pain frequency was 2.7% (95% CI: 1.5-4.9). The most common cause was diabetic neuropathy. According to painDETECT, the mean overall pain intensity was 5.7±2.4, being lower among patients receiving treatment. Pharmacological neuropathic pain treatment was used by 72.8% of patients and the most common drug was pregabalin. However, 70% of those receiving gabapentinoids were using ineffective doses. Besides, 4.6% of the patients were on medications which are not listed in neuropathic pain treatment guidelines. CONCLUSION: In our cohort, the neuropathic pain severity was moderate and the frequency was lower than the literature. Although there are many guidelines, high proportion of patients were being treated by ineffective dosages or irrational treatments.

The prevalence of tinea pedis and tinea manuum in adults in rural areas in Turkey.

The aim of this study was to determine the frequency of tinea pedis and manuum (dermatophyte infections of the hands and feet) in adults in rural areas of Turkey, the risk factors and self-administered treatment options. A total of 2,574 people living in a rural area were enrolled in the study. Participants were asked demographic data, hygienic habits in a questionnaire. KOH preparations and culture were performed from suspicious lesions. Medical and alternative therapy methods and former dermatophytosis diagnosis history were taken from the respondents with suspicious lesions. Microbiological samples were taken from 285 (11.1%) participants. Culture was positive in 109 (4.2%) of those. The most common agent was Trichophyton rubrum. The predisposing factors were found as age older than 40, male gender and obesity. Forty-nine (44.9%) of patients had taken a medical therapy, 56 (51.4%) had performed non-medical methods (cologne, Lawsonia inermis-Henna and softener creams). Patient's education about the treatment compliance is important.

Effects of colchicine on strength-duration properties of sensory and motor axons.

OBJECTIVE: The strength-duration time constant (SDTC) is a measure of axonal excitability and it can provide information about Na(+) channel function. In this study, we sought to examine the changes in the SDTCs of motor and sensory fibers of the median nerve in patients taking colchicine, which affects axoplasmic flow and may result in axonal neuropathy. METHODS AND RESULTS: The SDTCs of motor and sensory fibers of 29 patients who had been taking colchicine were measured following stimulation of the right median nerve at the wrist. The results were compared with ten healthy age-matched subjects. No significant differences were found between the groups. CONCLUSIONS: The lack of any effect on the SDTC by colchicine might have been due to the fact that axonal degeneration caused by colchicine affects the Na(+)-K(+) ATP pump or that it affects internodal channels other than nodal channels.

Joubert syndrome associated with new MRI findings and posterior reversible encephalopathy syndrome.

Joubert syndrome (JS) is an inherited disorder characterized by transient episodic hyperpnea, ataxia, and vermian hypoplasia. Typical imaging findings of JS include hypoplasia or aplasia of the cerebellar vermis, thick and elongated superior cerebellarpeduncles and an abnormally deep interpeduncular fossa with 'molar tooth sign'. We present a case of JS associated with deep cerebral sulci and fissures, polymicrogyria, and additional findings of posterior reversible encephalopathy syndrome associated with renal involvement.

Lyme disease presenting as subacute transverse myelitis.

Lyme disease (borreliosis) is a systemic illness resulting from infection with the spirochete Borrelia burgdorferi. It is transmitted to humans by the bites of infected ticks belonging to several species of the genus Ixodes. After the bacteria enter the body via the dermis, most patients develop the early, localised form of Lyme disease, which is characterised by erythema migrans and influenza-like symptoms. This disease may also affect the heart, nervous system and joints. The neurological findings of this disease may include peripheral and central nervous system signs. A 21-year-old woman attended a family medicine outpatient clinic complaining of unexplained pain and muscle power loss in her lower extremities. The problem had started in her right leg 3 months earlier and worsened in the last week. She had a neurology consultation and was hospitalised. Her neurological examination revealed bilateral facial paralysis and sensory impairment. Immunoglobulin M antibody to B. burgdorferi was positive on Western blotting in both serum and cerebrospinal fluid. The patient was diagnosed with subacute neuroborreliosis and treated.

Myeloneuritis due to acute organophosphate (DDVP) intoxication.

Given the importance of agriculture and widespread use of pesticides, intoxication due to organophosphate insecticides is common in Turkey. Organophosphorus compounds may cause late-onset distal polyneuropathy occurring 2 or more weeks after the acute exposure. An 18-year-old woman and a 22-year-old man were admitted to the hospital with weakness, paresthesia, and gait disturbances at 35 and 22 days, respectively, after ingesting dimethyl-2,2-dichloro vinyl phosphate (DDVP). Neurological examination revealed weakness, vibration sense loss, bilateral dropped foot, brisk deep tendon reflexes, and bilaterally positive Babinski sign. Electroneurography demonstrated distal motor polyneuropathy with segmental demyelination associated with axonal degeneration prominent in the distal parts of both lower extremities.

Myasthenia gravis and psoriasis vulgaris.

Myasthenia gravis is a rare autoimmune disorder in which antibodies form against acetylcholine nicotinic postsynaptic receptors at the myoneural junction. Psoriasis vulgaris is a chronic, recurring, and an inflammatory skin disease. Myasthenia gravis and psoriasis are both autoimmune diseases and correlated with specific human histocompatibility antigens. In this report, a 53-year-old woman who has myasthenia gravis accompanied with psoriasis vulgaris is presented. To conclude, this association is extremely rare and the pathogenetic etiology was thought to depend on a generalized immunological disturbance.

Thyrotoxic hypokalaemic periodic paralysis in a Turkish population: three new case reports and analysis of the case series.

OBJECTIVE: Thyrotoxic hypokalaemic periodic paralysis (THPP) is an uncommon condition with intermittent episodes of muscle weakness and occasionally severe paralysis. THPP is a common complication of hyperthyroidism in Asian populations, and has also been reported in other ethnic groups including Caucasians. This study aimed to conduct an analysis of THPP in a Turkish population, and is to our knowledge the first analysis of a homogeneous Caucasian group. SUBJECTS: Forty cases with THPP were identified in the Turkish population. Three out of the 40 were new cases and were assigned as index cases. Two cases were not included in the analysis because of lack of data. RESULTS: THPP was diagnosed in 10 cases during the first attack and was observed to have a significant shorter complete recovery time statistically in this group (P < 0.01). The majority of cases were hypokalaemic, while there were two normokalaemic cases. Classification of the cases according to their potassium (K) levels revealed that the group with K levels < 2.5 mEq/l had a statistically longer amelioration time than the group with K levels > or = 2.5 mEq/l. When the cases were classified according to intravenous or oral application of K, the mean amelioration time was 6.8 +/- 3.6 h for the intravenous group and 13.1 +/- 7.6 for the oral group. Mean complete recovery times of the groups were 29.4 +/- 16.2 h and 52.8 +/- 18.0 h, respectively. The intravenous group had a shorter amelioration time and complete recovery time, and both were statistically significant (P < 0.05 for each). CONCLUSIONS: THPP may be seen among Caucasians. Diagnosing THPP during the first attack might decrease the recovery time. The level of hypokalaemia seems to affect the recovery time and initial low K levels may lead to more deterioration in a patient's health compared with mild or near-normal levels. Intravenous, rather than oral, application of K may be advantageous for shortening both the amelioration and complete recovery times.