Clinical predictors of acute radiological pneumonia and hypoxaemia at high altitude

Fast breathing has been recommended as a predictor of childhood pneumonia. Children living at high altitude, however, may breathe faster in response to the lower oxygen partial pressure, which may change the accuracy of prediction of a high respiratory rate. To assess the usefulness of clinical manifestations in the diagnosis of radiological pneumonia or hypoxaemia, or both, at high altitude (2640 m above sea level), 200 children aged 7 days to 36 months presenting to an urban emergency room with cough lasting less than seven days were studied. Parents were interviewed and the children evaluated using standard forms. The results of chest radiographs and pulse oximetry obtained after clinical examination were interpreted blind. Radiological pneumonia and haemoglobin oxygen saturation < 88% were used as 'gold standards'. One hundred and thirty (65%) and 125 (63%) children had radiological pneumonia and hypoxaemia respectively. Crepitations and decreased breath sounds were statistically associated with pneumonia, and rapid breathing as perceived by the child's mother, chest retractions, nasal flaring, and crepitations with hypoxaemia. The best single predictor of the presence of pneumonia is a high respiratory rate, although the results are not as good as those reported by other studies. A respiratory rate > or = 50/minute had good sensitivity (76%) and specificity (71%) for hypoxaemia in infants. Hypoxaemia had a good sensitivity and specificity for pneumonia mainly in infants (83% and 73%, respectively). Logistic regression analysis showed that decreased or increased respiratory sounds and crepitations were associated with pneumonia, and that hypoxaemia is the best predictor when auscultatory findings are excluded. These results suggest that some clinical predictors appear to be less accurate in Bogota than in places at lower altitude, and that pulse oximetry can be used for predicting pneumonia.

[Findings of digital intensive or bed lung radiographs at the monitor vs. hard copy: a clinical ROC study]

45 bedside chest examinations acquired with storage phosphorus radiography, were displayed on a viewing box as single-format hard copies and at a high-performance digital reporting console. 6 observers performed an ROC study. For the pathologies under question, significantly better results were shown in monitor reporting due to pneumonic infiltration whereas no significant differences were found for pulmonary or mediastinal masses, or for pneumothoraces.

Localized reduction in 123I-MIBG accumulation in the lung

A patient with old myocardial infarction underwent 123I-MIBG scintigraphy to evaluate the adrenergic nerve system in the heart following the treatment of pneumonia. Decreased accumulation of MIBG was observed in the right lower lung field, corresponding to the area affected by pneumonia, as well as in the left ventricle with myocardial infarction. 99mTc-MAA lung perfusion scan demonstrated hypoperfusion in the region of reduced MIBG uptake. Regional decrease in MIBG uptake in the lung is considered to suggest lung pathology, and lung perfusion scan is recommended to discriminate selective endothelial damage from loss of vascular bed.

Invasive zygomycosis due to Conidiobolus incongruus

During the past decade, an increasing spectrum of pathogenic Zygomycetes fungi have caused infections in humans. The preponderance of these deeply invasive infections have been caused by members of the order Mucorales. However, deeply invasive zygomycoses due to genera of the order Entomophthorales (Conidiobolus species and Basidiobolus species) have seldom been reported. We describe a granulocytopenic patient with pulmonary and pericardial zygomycosis due to Conidiobolus incongruus, describe this organism's susceptibility to antifungal agents, characterize its diagnostic microbiological characteristics, and review previously reported cases of deeply invasive zygomycosis due to Conidiobolus species. In immunocompromised patients, C. incongruus is an uncommon but highly invasive fungal pathogen that may be resistant to amphotericin B and can be distinguished from other Zygomycetes fungi by characteristic mycological features.

A clinical profile of chronic bacterial pneumonia. Report of 115 cases

OBJECTIVE

To review the clinical presentation, radiology, microbiology, and response to therapy of patients with chronic bacterial pneumonia.

DESIGN

A retrospective analysis.

SETTING

An urban tertiary care medical center.

PARTICIPANTS

One hundred fifteen patients with pulmonary and/or constitutional symptoms of at least 1 month's duration with 4,000 or more colony-forming units (CFUs) of a single bacterial species identified by quantitative culture obtained via fiberoptic bronchoscopy.

MEASUREMENTS

Charts were analyzed for presence or absence of any predisposing illness, symptoms at presentation, roentgenographic abnormalities, microbiologic results, findings at fiberoptic bronchoscopy, and results of therapeutic intervention.

RESULTS

Sixty-five percent of patients with chronic bacterial pneumonia had a predisposing disease, 35 percent were "normal." Cough, fatigue, dyspnea, and weight loss were predominant symptoms in both groups. Bronchogenic carcinoma was newly diagnosed in 16 patients (14 percent). Haemophilus influenzae or alpha-hemolytic streptococcus was isolated in 68 percent of patients. Risk of recurrence of infection was inversely associated with duration of therapy in both groups.

CONCLUSIONS

Chronic bacterial pneumonia is more common than previously recognized. It occurs in patients with and without a predisposing illness. Clinical presentation, roentgenographic appearance, and bacteriology are similar between the two groups. Cure requires prolonged antibiotic therapy.

[Candida glabrata pneumonia in a non-immunosuppressed patient: diagnostic imaging with digital luminescence radiography and CT]

Pneumonias caused by Candida glabrata are extremely rare and occur almost exclusively in immunocompromised patients. We report an atypical case of Candida glabrata pneumonia in a non-immunocompromised patient and describe the imaging findings on digital radiography and computed tomography.

Radiologic assessment after lung transplantation

Imaging studies play a major role in patients undergoing lung transplantation. These patients are subject to unusual problems, such as the reimplantation response, acute rejection, bronchiolitis obliterans, ischemia-induced airway complications, and immuno-suppression-associated lymphoma. In addition, these patients are also subject to all of the usual problems associated with thoracic surgery, including atelectasis, infection, pneumothorax, and pleural effusion, all conditions for which radiologic assessment is crucial.

Helical computed tomography of the thorax. Clinical applications

Intuitively, any technique that minimizes the effects of respiratory motion, eliminates misregistration between scans, minimizes intravenous contrast requirements, and allows high quality multiplanar and 3-D image reconstruction is likely to have a tremendous impact on conventional notions concerning routine thoracic CT. Helical scanning is already of proved efficacy for vascular and airway imaging as well as for identifying and characterizing pulmonary nodules. It may be anticipated that the indications for the use of helical imaging will continue to expand. Of particular interest is the ongoing development of reconstruction algorithms that allow high-quality images to be obtained with rapid table incrementation while simultaneously reducing radiation exposure. Given the intrinsically high contrast of structures within the thorax coupled with the disadvantages that result from respiratory motion, it is not unreasonable to conclude that within the near future volumetric techniques will be the standard for nearly all CT applications within the thorax.

Ultrafast computed tomography of the chest

Improvements in scan speed and resolution are changing the role of the pulmonary imager. An understanding of airway mechanics and blood flow physiology is required to take full advantage of the new technology. Assessment of regional airflow and blood flow provides information that is currently unavailable from clinical tools.

Causes of fever and pulmonary densities in patients with clinical manifestations of ventilator-associated pneumonia

BACKGROUND

Ventilator-associated pneumonia, a leading cause of sepsis in patients with acute respiratory failure, is difficult to distinguish clinically from other processes affecting patients receiving mechanical ventilation. We conducted a prospective study of patients with suspected ventilator-associated pneumonia to identify the causes of fever and densities on chest radiographs and to evaluate the diagnostic yield and efficiency of tests used alone and in combination.

METHODS

The 50 patients entered into the study underwent a systematic diagnostic protocol designed to identify all potential causes of fever and pulmonary densities. Diagnoses responsible for fever were established by strict diagnostic criteria for 45 of the 50 patients. The prevalence of specific conditions and diagnostic yield of individual tests were used to formulate a simplified diagnostic protocol.

RESULTS

The diagnostic protocol identified 78 causes of fever (median 2 per patient). Infections were the leading causes of fever and pulmonary densities. Of the 45 patients with fever, 37 had one or more infections identified (67 sources). Most infections (84 percent) were one of four types:pneumonia, sinusitis, catheter-related infection, or urinary tract infection. Ventilator-associated pneumonia occurred in only 42 percent. All but nine infections (87 percent) were directly or indirectly related to insertion of a catheter or a tube. Concomitant infections were frequent (62 percent), particularly in patients with sinusitis (100 percent), catheter-related infections (93 percent), and pneumonia (74 percent). Of concomitant infections, 60 percent were caused by a different pathogen. Noninfectious causes of fever were more common in the 22 patients with adult respiratory distress syndrome. Histologically proved pulmonary fibroproliferation was the only cause of fever in 25 percent of patients with adult respiratory distress syndrome. Radiographic densities were caused by an infection in only 20 patients (19 pneumonia, 1 empyema). In more than 50 percent of the 25 patients without adult respiratory distress syndrome, congestive heart failure, and atelectasis were the sole causes of pulmonary densities, and fever always originated from an extrapulmonary site of infection. Used in combination, bronchoscopy with protected sampling, computed tomographic scan of the sinuses, and cultures of maxillary sinus aspirate, central intravenous or arterial lines, urine, and blood identified 58 of the 78 sources of fever (74 percent).

CONCLUSIONS

The observations in this study document the complex nature of acute respiratory failure and fever and underscore the need for accuracy in diagnosis. The frequent occurrence of multiple infectious and noninfectious processes justifies a systematic search for source of fever, using a comprehensive diagnostic protocol. A simplified diagnostic protocol was devised based on the diagnostic value of individual tests.

Bordetella bronchiseptica pneumonia in a patient with AIDS

Bordetella bronchiseptica is recognised as a respiratory tract pathogen in many mammalian species, but has rarely been implicated in human infection. A case is reported of pneumonia caused by B bronchiseptica in a patient suffering from acquired immunodeficiency syndrome (AIDS).

Cat-transmitted fatal pneumonic plague in a person who traveled from Colorado to Arizona

Plague, primarily a disease of rodents and their infected fleas, is fatal in 50% of infected humans if untreated. In the United States, human cases have been concentrated in the southwest. The most common modes of plague transmission are through flea bites or through contact with infected blood or tissues; however, primary pneumonic plague acquired from cats has become increasingly recognized. We report on the case investigation of a patient, presumably exposed to a plague-infected cat in Colorado, who presented with gastrointestinal symptoms, and subsequently died of primary pneumonic plague. Public health officials should be vigilant for plague activity in rodent populations, veterinarians should suspect feline plague in ill or deceased cats, and physicians should have a high index of suspicion for plague in any person who has traveled to plague enzootic areas.

Quinidine-induced reversible pneumonitis

We report a patient who developed fever and rapidly progressing lung infiltrates 4 days after the beginning of continuous quinidine sulfate therapy. The fever disappeared during the following 48 h and the pneumonitis slowly resolved over the next month once quinidine therapy was stopped. The diagnosis of quinidine-induced pneumonitis, which has not previously been reported in the literature (to our knowledge), was confirmed by means of a rechallenge with quinidine.

[Radiographic evaluation of the clinical course and outcome in acute pneumonias]

The authors review the data of x-ray functional examinations of 525 patients with acute parenchymatoys pneumonia, 393 convalescents after pneumonia 3-6 months after the disease and analyze 480 case histories of patients, hospitalized for acute pneumonia 10 years ago. Development, x-ray picture, and resolution of the process are described. Besides traditional x-ray examination, roentgenography in oblique projections and pulmonary sonography are recommended in order to specify the anatomic changes in the lungs. Functional peculiarities of the involved and intact lungs were studied. Altogether 92.4% of convalescents are discharged from hospital with changed pulmonary pattern and, rather often, with infiltration of the parenchyma in the subpieural portions of the involved lobes and segments, as well as with disordered respiratory function of the lungs. Unfavorable outcomes in remote period after disease (pneumosclerosis, pneumocirrhosis, emphysema, chronic pneumonia) are observed mainly in subjects discharged from hospital before complete clinical cure.

Risk factors for pneumonia among children in a Brazilian metropolitan area

OBJECTIVE

To investigate risk factors for pneumonia for infants < 2 years of age.

DESIGN

Hospital-based, case-control study with neighborhood control subjects.

SETTING

Urban area in southern Brazil.

SUBJECTS

Five hundred ten infants with radiologically confirmed pneumonia who were admitted to a pediatric hospital. One age-matched neighborhood control subject was selected for each case.

RESULTS

Multiple conditional regression modeling was used to control for confounding, taking into account the hierarchical relationships between risk factors. The incidence of radiologically confirmed pneumonia was associated with low paternal education, the number of persons in the household, young maternal age, attendance at day-care centers, low birth weight and weight-for-age, lack of breast-feeding and of non-milk supplements, and a history of previous pneumonia or wheezing. Day-care center attendance showed the highest risk, with an adjusted odds ratio of 11.75.

CONCLUSIONS

In addition to continued efforts toward appropriate case management, actions directed against the above risk factors may help prevent the major cause of deaths of children younger than 5 years.

Accurate contiguous sections without breath-holding on chest CT: value of respiratory gating and ultrafast CT

OBJECTIVE

To image truly contiguous CT sections without breath-holding, we developed a respiratory-gating device combined with ultrafast CT. The purpose of this study was to evaluate the utility of this system, especially focusing on the contiguity of the images.

SUBJECTS AND METHODS

In 37 patients, we obtained respiratory-gated scans and breath-hold scans with 6-mm collimation and 6-mm incrementation (19 patients) and with 3-mm collimation and 3-mm incrementation (18 patients). We compared these two sets of images with respect to quality and contiguity. In nine patients who could not hold their breath because of dyspnea or infancy, we obtained only respiratory-gated scans with 3-mm collimation and 3-mm incrementation. Our respiratory-gating device was composed of a commercial ECG and respiratory monitor, a triggering device, an original amplifier, and an original switching unit. It was designed to control the scan timing of an ultrafast CT scanner at a user-selected level of the respiratory curve obtained with transthoracic impedance plethysmography.

RESULTS

The respiratory-gated images were equal in quality to the breath-hold images in 31 of the 37 patients who had both sets of images. In 15 of 19 patients who had 6-mm-thick sections and in 11 of 18 patients who had 3-mm-thick sections, satisfactory contiguous images of bronchi and pulmonary vessels were obtained. Additionally, in seven of the nine patients who could not hold their breath, satisfactory contiguous sections were obtained.

CONCLUSION

The respiratory gating system combined with ultrafast CT can provide contiguous CT scans without breath-holding or patients' cooperation. The procedure could improve the diagnostic accuracy of CT, especially in severely ill patients, infants, and senile patients.

Comparison of the clinical and radiographic diagnosis of paediatric pneumonia

Pneumonia causes 3.2 million deaths per year in children under 5 years old according to the World Health Organization. In spite of the number of deaths, no single clinical or radiological definition for the diagnosis of pneumonia is widely accepted. To determine the extent of agreement between clinical and radiographic diagnoses of pneumonia, we compared the clinical diagnoses made by an experienced paediatrician with diagnoses based on a paediatric radiologist's interpretation of chest radiographs. In 226 children with respiratory illness brought to a hospital outpatient department in Lesotho, pneumonia was the clinical diagnosis for 39 and the radiographic diagnosis for 40; however, for only 19 children did the 2 diagnoses concur. Children with a radiographic diagnosis of pneumonia tended to have been ill longer, to be older, and to be more likely to have a technically adequate radiograph than children with negative radiographs, independent of the clinical diagnosis. In this comparison, radiographic and clinical diagnoses for pneumonia differed substantially. Some of this discrepancy may be explained by misinterpretation of suboptimal films and different rates of evolution of radiographic and clinical manifestations of pneumonia. Radiographic studies and clinical evaluations produced complementary data in this evaluation: of the 60 children with clinical or radiographic evidence of pneumonia, 14 would not have been treated with an antimicrobial drug without radiography. Wider availability of radiography is needed to supplement clinical examination for the diagnosis of pneumonia, and may be particularly valuable in children more than 18 months old, those who have been ill for more than 6 d, and those with fever.

Listeria monocytogenes and severe newborn respiratory failure supported with extracorporeal membrane oxygenation

OBJECTIVE

To determine the efficacy of extracorporeal membrane oxygenation (ECMO) in newborn infants with early-onset Listeria monocytogenes infection, necrotizing pneumonia, and severe respiratory failure.

DESIGN

Patient series.

SETTING

ECMO referral centers.

PARTICIPANTS

The Extracorporeal Life Support Organization Registry database of patients supported with ECMO between 1975 and 1991.

INTERVENTION

ECMO.

MEASUREMENTS AND RESULTS

Nine neonates were identified who were supported with ECMO for severe respiratory failure associated with L monocytogenes infection. Microbiologic studies demonstrated L monocytogenes organisms in the blood of all infants, and pneumonia was diagnosed by roentgenogram and/or isolation of L monocytogenes organisms in tracheobronchial secretions. All infants experienced progressive respiratory deterioration by age 36 hours and were placed on venoarterial bypass by 96 hours, having met institution-based criteria predictive of 80% to 90% mortality. The duration of ECMO for patients with Listeria infection (median, 210 hours; range, 137 to 454 hours) was prolonged compared with the duration of ECMO for neonates in all other registry diagnostic categories (median, 114 hours; range, 1 to 744 hours; N = 5146, P = .035). Six of the nine infants recovered completely.

CONCLUSIONS

These data suggest that ECMO is efficacious in patients with severe respiratory failure secondary to Listeria sepsis. Prolonged time on bypass should be expected when Listeria sepsis is associated with severe necrotizing pneumonia.

Clinical signs of pneumonia in infants under 2 months

To determine clinical signs that can predict pneumonia (confirmed by radiography) in infants under 2 months of age, 101 infants with pneumonia and 150 with an upper respiratory infection (but not pneumonia) were studied. Ten infants with pneumonia and 15 with an upper respiratory infection did not have the cough and/or difficult (or rapid) breathing that are recommended as 'entry criteria' by the World Health Organisation (WHO). The remaining infants met WHO entry criteria; in them sensitivity and specificity of respiratory rate > or = 60/min and/or severe chest indrawing to diagnose pneumonia was 85% and 97% respectively. Addition of four non-specific signs (stopped feeding well, looked sick, temperature < or = 38 degrees C, and abdominal distension) to respiratory rate > or = 60/min and/or chest indrawing for case identification resulted in a 7% gain in sensitivity but 22% loss of specificity. Addition of nasal flaring improved the sensitivity by 6% without loss of specificity. However, the non-specific signs were the only clue to diagnosis in five infants weighing < or = 2500 g. At age < 7 days, a weight < or = 2500 g and cyanosis were associated with significantly higher risk of mortality. These findings support the use of a respiratory rate > or = 60/min and/or chest indrawing for identification of pneumonia, and suggest addition of nasal flaring to the criteria for case identification in infants under 2 months with cough and/or difficult or rapid breathing.

[Lung infections in acquired immunodeficiency. Clinico-radiologic correlations]

Over the last decade the number of subjects with acquired immunodeficiencies has markedly increased; this phenomenon depends on both the large number of patients receiving organ transplants or antiblastic therapy and the spread of infections caused by the HIV virus. In 70-90% of these patients primary diseases include different pulmonary infections, relative to the type and degree of immune compromission. Pathogenic or, in most cases, opportunistic germs are responsible for severe pneumonia whose mortality rate can top 50%. Since prognosis depends on the promptness of treatment, the diagnosis of nature must be made quickly by integrating clinical and diagnostic findings with laboratory and instrumental results. Conventional chest radiology plays a major role as the first step in a diagnostic iter which can now include rather sensitive techniques--e.g., equalized chest films. CT and nuclear medicine often represent the necessary diagnostic complements but, in some cases, etiology can be diagnosed only with such invasive procedures as lung biopsy. The authors reviewed the current data on the diagnostic imaging findings of pulmonary infections caused by common germs, by Pneumocystis carinii mycobacteria, mycetes and viruses in immunocompromised patients, integrating their personal experience with literature data.

Community acquired pneumonia in adults in Addis Abeba: etiologic agents, clinical and radiographic presentation

We prospectively studied 110 adult patients coming to Black Lion Hospital between August 1987 and July 1989 with community acquired pneumonia (CAP) for various etiologic agents and clinical and radiographic presentation. Streptococcus pneumoniae was the most common offending pathogen in 72% and 67.5% from sputum and lung aspirate (LA) Gram stain respectively, and in 41% by pneumococcal serotyping of sputum. Blood and LA culture grew Streptococcus pneumoniae in 4 (6%), Staphylococcus aureus in 4 (6%), Enterobacteriaceae in (3%), Pseudomonas, Klebsiella and Streptococcus viridans in one case each. Non-bacterial pathogens included Mycoplasma pneumoniae in 3 (3%), Influenza A in 4 (4%), Influenza B in 3 (3%) and psittacosis/LGV in 4 (4%). Fever, cough, chest pain, tachypnea and coarse crepitations/bronchial breathing were the most common presenting signs and symptoms. Thirty per cent had associated diarrhoea and vomiting initially and 9% had altered state of consciousness at admission. Six patients came in a state of shock. Thirty-nine per cent had underlying illnesses. Ninety-three per cent had either segmental or lobar consolidation. Parapneumonic effusion occurred in 14%. The mortality was 11%. Tachypnea, the presence of underlying illness, altered state of consciousness, extreme leucocytosis and the presence of bilateral and multilobar lung involvement were found to be signs of poor prognosis. Our finding is similar to those from other African countries, except that we are reporting psittacosis/LGV for the first time in Africa.