Rapid and robust bacterial species identification using hyperspectral microscopy and gram staining techniques

Gram staining can classify bacterial species into two large groups based on cell wall differences. Our study revealed that within the same gram group (gram-positive or gram-negative), subtle cell wall variations can alter staining outcomes, with the peptidoglycan layer and lipid content significantly influencing this effect. Thus, bacteria within the same group can also be differentiated by their spectra. Using hyperspectral microscopy, we identified six species of intestinal bacteria with 98.1% accuracy. Our study also demonstrated that selecting the right spectral band and background calibration can enhance the model's robustness and facilitate precise identification of varying sample batches. This method is suitable for analyzing bacterial community pathologies.

Unveiling Gram-Ghost Cells: A Crucial Aspect of Gram Staining in the COVID-19 Era

The term "Gram-ghost appearance" refers to mycobacteria's unique Gram staining characteristics. Recognizing Mycobacterium tuberculosis as a potential pathogen in respiratory infections, especially in the elderly during the COVID-19 pandemic, is critical. This case highlights the pivotal role of Gram staining in diagnosis, particularly when COVID-19 tests consistently show negative results. Recognition of Gram-ghost bacilli facilitated prompt tuberculosis diagnosis, emphasizing the enduring diagnostic value of Gram staining, especially in the COVID-19 era.

Occult Bacteremia Caused by Enterococcus-Associated Pyuria in an Elderly Man

We report a case of Enterococcus-associated pyelonephritis in a 74-year-old Parkinson's patient. He showed constipation, a mild fever, and altered consciousness. Blood cultures revealed Gram-positive cocci (GPC), prompting vancomycin treatment. Urinary Gram staining confirmed pyelonephritis, underscoring its diagnostic utility in elderly patients with vague symptoms. Enterococcus faecalis infections can be insidious, with the potential for organ abscesses and persistent fever. Due to nuanced presentations of Gram-positive infections versus Gram-negative ones, diagnosis can be delayed, risking sepsis. Gram-staining urine is vital, especially in older patients, as untreated Gram-positive bacteremia elevates mortality. Given our aging population and their comorbidities, Gram staining's role in quick antibiotic administration is crucial. Hence, its integration into community hospitals is advocated. This case emphasizes early detection and treatment of GPC infections in the elderly and endorses Gram staining for prompt diagnosis of Enterococcus-associated pyelonephritis.

Risk Factors and Microbiological Studies on <i>Streptococcus pneumoniae</i> Isolated from Pneumonia Patients of Quetta Balochistan

BACKGROUND AND OBJECTIVE

Pneumococcal diseases remain a major cause of morbidity and mortality worldwide. Streptococcus Pneumoniae causing pneumonia in India, Pakistan, Bangladesh and Afghanistan in children under 5 years of age and older adults. Therefore; the present research was design to study the different microbiological aspects of Streptococcus pneumoniae.

MATERIALS AND METHODS

A total of 480 sputum samples were collected from pneumonia patient at different government hospitals of Quetta. The detail of patient's gender, age, economical status and educational status were taken on performa. Sputum samples were inoculated into selective strep agar Streptococcus pneumonia colonies were observed on plates and confirmed through different biochemical tests and PCR.

RESULTS

Total 480 samples were collected in which 36.6% were Streptococcus pneumoniae positive and 63.3% were negative. The sex wise ratio showed that female (24.10%) were more affected with pneumoniae as compare to male (12.50%). The pneumonia infection age wise distribution was 9% in 1-10 years old patients, 16% in 10-20 years old patients and 11% in 20-30 years old patients. The status wise distribution of pneumonia infection showed that lower class (16%) was more affected as compare to middle class and higher class of Quetta. The percentage of pneumonia infection in hazara race was 14%, in Pathan 8.30%, in Punjabi 7.60% and in Baloch 6.60%. It was seen that illiterate patients were more affected with pneumonia infection (28.3%) than literate (8.3%). The Streptococcus pneumoniae was confirmed through gram staining, different biochemical tests, different sugar fermentation tests and PCR. Whereas confirmed by PCR showed clear band of 329 kb of ply gene.

CONCLUSION

It was concluded that the rate of pneumonia infection was high in female and lower class was more affected with pneumonia.

Corynebacterium propinquum bronchopneumonia in a child with ataxia telangiectasia

Nondiphtherial Corynebacterium species isolated from clinical specimens are usually considered as contaminants by many clinicians when reported by microbiologists. However, an increasing number of studies have confirmed the importance of Corynebacterium spp. in the etiology of a variety of infectious processes. In this report, we present a case of bronchopneumonia caused by Corynebacterium propinquum. The infection occurred in a seven-year-old child who had a history of immunosuppression due to ataxia telangiectasia. The purulent sputum of the patient yielded a large number of polymorphonuclear leucocytes with abundant gram-positive coryneform bacilli in gram staining and pure growth of coryneform bacteria in culture. Definitive identification as C. propinquum was made by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing. C. propinquum should be recognized as a potential pathogen and included in the etiologic diagnostic algorithm, particularly in patients with immunosuppressive conditions.

Viability of bacteria in dental calculus - A microbiological study

Aim:

The aim of this study was (1) To investigate the viability of bacteria within supragingival and subgingival calculus, (2) To examine motility of bacteria, and (3) To identify bacterial morphotypes in calculus.

Materials and Methods:

Supra and subgingival calculus were harvested from 30 subjects having clinical evidence of chronic inflammatory periodontal disease and were divided into two groups. Samples from both groups were immediately transported to the Department of Microbiology for gram staining, acridine orange staining, bacterial culture and to the Department of Oral Pathology for dark field microscopy.

Results:

Gram staining revealed presence of bacteria within the samples.Dark field microscopic examination revealed presence of filamentous organisms, spirochetes, and motile short bacilli. Acridine orange fluorescent stain showed that the viable bacteria appeared apple green. Bacterial culture revealed presence of a variety of aerobic organisms.

Conclusion:

From the results, it appeared that viable bacteria were present within calculus especially within internal channels and lacunae.