Coinfection of Pseudomonas and Aspergillus has not been previously reported in patients with chronic obstructive pulmonary disease (COPD). A middle-aged, thinly built woman (Body Mass Index: 18.1 kg/m²) who smokes bidi (a type of tobacco) and has a history of exposure to open log fires for cooking, has been suffering from COPD for the last 4 years. She has been taking inhaled betamethasone and tiotropium. Additionally, she had uncontrolled diabetes for a few months. She presented with fever, productive cough, shortness of breath and chest pain for 5 days. She required non-invasive ventilation support for type-2 respiratory failure. Chest X-ray and CT confirmed pneumonia, cavities and abscesses in both lungs. Repeated sputum and bronchoalveolar lavage confirmed coinfections with Pseudomonas aeruginosa and Aspergillus fumigatus, respectively. Along with supportive therapy, she was treated with tablet levofloxacin and injection amikacin for 6 weeks based on culture sensitivity reports, and capsule itraconazole for 6 months. She recovered completely to her baseline COPD and diabetes status. This case study confirms that coinfections can occur in COPD and diabetes, highlighting the need for clinicians to be vigilant for the possibility of such symbiotic coinfections.

A male patient in his 40s who had been unwell for months with fever of unknown origin and clinicopathological features suspicious for haemophagocytic lymphohistiocytosis presented to hospital with worsening subacute shortness of breath. CT pulmonary angiogram demonstrated ground glass changes involving all lung lobes with an apicobasal gradient. These changes, combined with long-term steroid exposure for granulomatous hepatitis without pneumocystis prophylaxis, raised concern for pneumocystis jirovecii pneumonia (PJP). A subsequent bronchoscopic lavage specimen was positive on PCR for PJP and the patient was started on appropriate therapy. Clinical and radiological changes initially improved but after completion of therapy, symptoms and radiological abnormalities returned. Retreatment with second-line treatment resulted again in initial improvement followed by relapse with acute deterioration. Further investigations for an alternate diagnosis were made, with a surgical lung biopsy performed finally revealing immunosuppression-related Epstein-Barr virus positive large B cell lymphoma with lymphomatoid granulomatosis of grade 3 pattern.

We present the case of a man in his early 50s who presented with a history of fever, malaise and jaundice. Initial investigations showed liver and renal dysfunction with no discernible cause for the septic process. On starting intravenous antibiotics, the patient developed a septic-shock-like reaction requiring transfer to intensive care. A diagnosis of leptospirosis was eventually established through an extensive and thorough history leading to a stepwise approach to investigations. Treatment targeting leptospirosis was delivered with noticeable clinical improvement.

We present the first published case of simultaneous pneumonitis and immune thrombocytopenic purpura secondary to primary cytomegalovirus (CMV) infection in an immunocompetent patient. Treatment with oral valganciclovir for 2 weeks successfully led to complete clinical recovery. CMV is traditionally associated with infection in immunocompromised patients and neonates; however, evidence of severe CMV infections in immunocompetent hosts is emerging. It is important to highlight the broad range of clinical presentations of CMV infections to prevent diagnostic delay and associated morbidity and expense.

Mucosa-associated lymphoid tissue (MALT) lymphoma is an uncommon extranodal low-grade B-cell lymphoma. Pulmonary MALT lymphomas originate from bronchial MALT and are also referred to as bronchial-associated lymphoid tissue lymphomas. MALT lymphomas of the lung are slow-growing tumours and usually present as asymptomatic chronic alveolar opacities visible on chest radiographs or with non-specific pulmonary symptoms. Here we described a case of a male patient in his early 50s with cough and chest pain for 4 years. His CT chest scan showed consolidation in the lingula and left lower lobe. Histopathology of the specimen obtained from cryobiopsy of the lung lesion showed a dense monomorphic lymphoid infiltrate, and immunohistochemistry confirmed the diagnosis of MALT lymphoma. The prognosis of pulmonary MALT lymphomas is good with >80% 5-year survival rates. This case highlights that MALT lymphoma should be considered as a differential diagnosis while evaluating cases with non-resolving consolidation.

Lemierre syndrome (LS) is referred to as the \'forgotten Disease\' owing to its rarity in the postantibiotic era with an estimated yearly incidence of 1/million population. The classic triad of LS includes internal jugular vein thrombosis, oropharyngeal infection and metastatic septic emboli. We present a case of typical LS with Fusobacterium and Prevotella infection, presenting with peritonsillar abscess and jugular vein thrombosis complicated by sepsis, acute hypoxic respiratory failure due to multiple pulmonary emboli and severe thrombocytopaenia in the absence of disseminated intravascular coagulation.

Methaemoglobinaemia occurs when iron in haemoglobin is oxidised into a form that cannot transport oxygen. At low levels, it is asymptomatic, though at rising levels symptoms arise from impaired oxygenation, and it can ultimately be fatal. While uncommon, it is important to consider in hypoxaemic COVID-19 patients, especially if they are not clinically improving on standard treatments and workup for other causes does not explain the ongoing hypoxaemia. It is often diagnosed through a mismatch in peripheral and arterial oxygen, with the former typically less than the latter. We present the case of a COVID-19 patient who was found to have methaemoglobinaemia due to dapsone use for Pneumocystic jirovecii pneumonia (PJP) prophylaxis while on chemotherapy. Dapsone was stopped and supplemental high-flow nasal cannula was provided, and methaemoglobin levels improved over a 5-day period. She was discharged to follow-up with her haematologist in the clinic.

A man in his 50s, with a history of night sweats and weight loss, presented acutely with dyspnoea and chest pain. Imaging revealed right middle lobe consolidation and a large pericardial effusion. The diagnosis of actinomycosis was made using endobronchial ultrasound-guided sampling from the pericardial effusion. An orthopantomogram demonstrated that the source was a large cavity in the left lower wisdom tooth. This tooth was extracted before the completion of his antibiotic course, and the patient made a full recovery. Cardiac actinomycosis is rare, and there are few case reports describing endobronchial ultrasound-guided sampling of pericardial fluid.

Empyema of the lung is an infection-induced collection of fluid in the chest cavity. Clostridium perfringens is a bacterium that inhabits the intestine and is a rare cause of empyema after abdominal surgery. A slow phase of infection, associated with C. perfringens empyema, has previously been reported in cases of similar infections. Herein, we present a case of C. perfringens empyema following abdominal surgery. The empyema was initially managed using oxygen supplementation, fluid drainage and antibiotic therapy.This initial therapy failed in the present case because multiple collections of infected fluid prevented the lungs from expanding, requiring decortication, a pulmonary operation to remove the inflammatory tissue from the walls of the lung and associated with the infection, to allow the lung to expand. Following this operation, the patient recovered baseline levels of breathing and oxygen supplementation.

A pregnant woman in her early 30s, at 20 weeks of gestational age, presented with recurrent haemoptysis, pleuritic chest pain and a productive cough of 6 months duration. She underwent CT pulmonary angiogram which demonstrated right pulmonary sequestration and right-sided consolidation. Pre-existing pulmonary comorbidities such as chronic inflammation, structural abnormalities or weakened blood vessels within the lungs can encourage the growth of abnormal blood vessels. During pregnancy, these dynamics can be further aggravated by increasing cardiac output to promote blood flow to the placenta and increasing oxygen delivery to the developing foetus. These changes likely cause increased blood flow to the pulmonary sequestration, resulting in haemoptysis. The patient was treated conservatively for community-acquired pneumonia with a course of oral amoxicillin 500 mg three times a day for 5 days, and she is doing well on follow-up.