Chlamydia pneumoniae infection in adults with chronic cough compared with healthy blood donors.

In a small uncontrolled study, persistent cough has recently been found to be associated with serological evidence of acute Chlamydia pneumoniae infection. In order to assess whether C. pneumoniae plays a role in chronic cough, the prevalence of C. pneumoniae infection in 201 adult patients with chronic cough was compared with the prevalence in 106 healthy blood donors without respiratory tract symptoms in the preceding 3 months. A microimmunofluorescence antibody test was used to determine C. pneumoniae antibodies in the immunoglobulin (Ig)M, IgG and IgA fractions. Further, nasopharyngeal aspirates from the 201 patients were examined for C. pneumoniae deoxyribonucleic acid by polymerase chain reaction (PCR). As judged by serology, nine patients (4%) and one control (1%) had acute C. pneumoniae infection, and 92 patients (46%) and 42 controls (40%) had previous or chronic C. pneumoniae infection. Of the nine patients with acute infection, three were C. pneumoniae PCR positive, and they all had an IgM antibody titre response. The remaining six patients had either an IgG antibody titre of > or =512 (five patients) or an IgA antibody titre of > or =512 (one patient). None of these six patients had detectable IgM antibodies. The mean cough period for the five IgG positive patients (10.8 weeks) was significantly longer than the mean cough period for the remaining patient population (6.4 weeks; p=0.004). It is concluded that Chlamydia pneumoniae infection was not statistically significantly more prevalent in patients with chronic cough than in healthy blood donors, and that Chlamydia pneumoniae appears to have a minor role in patients with chronic cough. Direct detection of Chlamydia pneumoniae by polymerase chain reaction on nasopharyngeal aspirates is highly correlated with detectable immunoglobulin M antibodies, but in the late stages of prolonged cough serological testing of immunoglobulin G and immunoglobulin A may be more beneficial for obtaining a microbiological diagnosis.

Mycoplasma contamination of Chlamydia pneumoniae isolates.

We examined 6 C. pneumonia isolates from The American Type Culture Collection (ATCC) and 2 Finnish isolates for Mycoplasma contamination. Three of the ATCC isolates and both of the Finnish isolates were Mycoplasma-contaminated. The contaminants were characterized by means of growth in BEa and BEg media, immunoblotting, polymerase chain reaction and pulsed field gel electrophoresis. Two of the 6 ATCC isolates [ATCC VR1355 (TWAR strain 2043) and ATCC VR1356 (TWAR strain 2023)] were infected with Mycoplasma hominis and 1 isolate [ATCC VR2282 (TWAR strain TW183)] was contaminated with both Mycoplasma hominis and Mycoplasma orale, whereas 3 of the ATCC isolates [ATCC VR1310, ATCC VR1360 (TWAR strain CM-1) and ATCC 53592 (TWAR strain AR39)] were not contaminated. The Finnish C. pneumoniae isolates Kajaani 6 and Parola were found to be contaminated with M. hominis and M. orale, respectively. The contamination of C. pneumoniae stock cultures, frequently used in the microimmunofluorescence test, with human pathogens, could pose a serious problem in C. pneumoniae serology.

Relative bradycardia in infectious diseases.

Relative bradycardia in infectious diseases is a poorly defined term. No exact and useful definition exists and the underlying mechanisms are unknown. Despite this, the term is often used in the literature and in clinical practice both as a clinical sign for an individual patient and as a characteristic feature of certain specific diseases. In this study a definition of relative bradycardia as a clinical sign in an individual patient and a definition of relative bradycardia as a characteristic feature of a specific disease were established based on a reference population comprising 673 patients with various infectious diseases. Relative bradycardia as a clinical sign in an individual patient held no predictive value regarding the likely type of infection. Relative bradycardia as a characteristic feature of specific disease was found for typhoid fever (P = 0.003), Legionnaire's disease (P = 0.005), and pneumonia caused by Chlamydia sp. (P = 0.0005), but not for mycoplasma pneumonia. It was not found for other pulmonary infections, infections caused by other Salmonella sp., other extracellular Gram-negative infections, or viral infections. Thus, relative bradycardia as a clinical sign has no predictive value for obtaining a tentative diagnosis, but relative bradycardia as a feature of specific disease is seen in typhoid fever, Legionnaire's disease, and pneumonia caused by Chlamydia sp. It seems that relative bradycardia as a feature of specific disease only occurs in diseases caused by organisms that are both Gram-negative and intracellular.

Rabbit sphincter of Oddi and duodenal pressure and slow-wave activity. Effects of cholecystokinin.

BACKGROUND: The presence of sphincter of Oddi (SO) slow waves has been noted in earlier studies on the effect of cholecystokinin (CCK) on the SO, but a more thorough description of changes in SO slow-wave and pressure activity induced by CCK is needed. METHODS: The SO and duodenum in anaesthetized rabbits were prepared with perfused catheters and bipolar electrodes. Increasing, successive doses of CCK (1/32 to 1/1 Ivy Dog Units (IDU)/kg) were administered intravenously every 15th min. The digitized recordings were scored on a computer in control and stimulatory CCK sequences. RESULTS: CCK had a significantly stimulatory effect on SO and duodenum when estimated as area below pressure peaks (p < 0.001), but quantitatively, this effect did not differ in the two organs (p = 0.59). CCK significantly decreased SO slow-wave frequency (p < 0.05), whereas a similar trend in duodenal slow-wave frequency failed to reach statistical significance. Most pressure peaks recorded from the SO were associated with only one slow wave ('simple peak'), but the incidence of broad, irregular peaks belonging to more than one slow wave ('complex peaks') was significantly higher in CCK sequences (p < 0.02). Spectral analysis of SO pressure and slow-wave activity confirmed the dominating one-to-one relation between SO slow-wave and pressure peaks up to 1/4 IDU/kg, but also showed the disturbance caused by the increasing number of complex peaks generated by doses of at least 1/2 IDU/kg. CONCLUSIONS: CCK increases SO and duodenal activity equally. Up to a CCK dose of 1/4 IDU/kg the SO slow-wave regulatory mechanism is undisturbed, but higher doses lead to a fall in slow-wave frequency and qualitative changes in the relation between SO pressure and slow-wave activity.

Rabbit sphincter of Oddi has a certain autonomy: characteristic features.

Simultaneous recordings of electromyography and manometry were obtained from rabbit sphincter of Oddi (SO) and duodenum. Three different patterns of activity were observed in SO and in duodenum: 1) a low-amplitude (less than 3 cm H2O) pattern of background oscillations with 2) superimposed high-amplitude (4-20 cm H2O) contractions and 3) occasional complex contractions consisting of an elevation of the basal pressure with superimposed smaller contractions. A certain SO autonomy was evident: 57.6% of SO pressure peaks could not be assigned to any duodenal activity. The distribution of SO pressure peak amplitudes could not be described by a simple normal distribution. The distribution of SO pressure peak amplitudes with concomitant duodenal activity differed from the overall distribution (p less than 0.001). Whereas a substantial part of SO pressure peaks greater than 4 cm H2O had no or low-amplitude corresponding duodenal pressure activity, duodenal pressure peaks greater than 4 cm H2O almost invariably were associated with SO pressure peaks. It is concluded that rabbit SO does possess a certain autonomy, but at the same time a close functional connection exists between the two compartments.

Rabbit sphincter of Oddi and duodenum are regulated by slow waves with a common basic-mode activity.

Simultaneous recordings of pressure and slow-wave activity were obtained from the sphincter of Oddi (SO) and the duodenum in anesthetized rabbits. Histographic analysis of the recordings was performed when the following criteria were fulfilled: 1) slow waves must be present in the EMG recordings from both compartments; and 2) only pressure recordings with sufficient pressure activity (greater than 50 peaks in 10 min) would be considered. Of 12 animals fulfilling the criteria for histographic analysis of 4 channels, a common basic-mode activity was found in all channels in 9 animals (75%). Of three animals fulfilling the criteria for histographic analysis of three channels, a common basic-mode activity was seen in all channels in all animals (100%). A correlation between the amplitude of the slow waves and the amplitude of the elicited pressure peaks in the SO was significant at a 5% level or better in 12 animals (80%). In some of the animals episodes of low-amplitude pressure activity was observed in the SO, occurring synchronously with slow waves devoid of spike activity. It is concluded that rabbit SO and duodenum are paced by slow waves with a common basic-mode activity in most animals. Slow waves may not only be the chief determinant of the contractile rhythm but may also have a certain influence on the force of the individual SO contractions. It is suggested that slow waves per se may be able to mediate contractile activity.

[Oddi's sphincter dysfunction]. / Sphincter Oddi dysfunktion.

Dysfunction of the sphincter of Oddi (SOD) is an uncommon condition which must be considered in cases of persistent pain in the upper abdomen following uncomplicated cholecystectomy, when disease in other organs, such as gastric ulcer, esophagitis and pancreatitis has been eliminated. The pathogenesis is not fully elucidated, but it is assumed that the cholecystectomy in some cases induces an increased tendency to spasm in the sphincter of Oddi (SO), and, perhaps in connection with an increased sensitivity to pressure elevations in the biliary tree, results in attacks of pain. Whether fibrosis (stenosis) of the SO due to instrumentation or passage of stones is part of the etiology is obscure. Endoscopic retrograde cholangiopancreaticography with papillary manometry should be performed in all cases where SOD is suspected. An elevated basal pressure in SO seems to be the best indicator of SOD. In cases unresponsive to conservative treatment, endoscopic sphincterotomy may be considered. This treatment is not finally evaluated, but apparently the effect is good, especially in patients with elevated basal pressure in SO. It is emphasized that the knowledge of the behavior and regulation of SO is incomplete and that this should be remembered when criteria for SOD are applied.

A model for simultaneous study of pressure and electric events in the rabbit sphincter of Oddi and duodenum.

An animal experimental model featuring simultaneous recordings of electromyography and pressure from the sphincter of Oddi (SO) and duodenum is demonstrated. On the basis of data from 10 rabbits, pressure recordings from the SO were shown to have phasic activity with an average basic pressure peak interval of 2.6 to 3.5 sec. Histographic analysis of SO pressure recordings showed a multimodal appearance, suggesting that the activity is paced. A substantial amount of overlap between SO and duodenal contractions was observed. As many as 30% of the pressure peaks recorded from the SO could not be assigned to a spike complex in the corresponding EMG tracings. It is suggested that combined recordings of EMG and pressure activity are needed to characterize fully the motility of the SO and duodenum.