Misdiagnosis of chronic pulmonary aspergillosis as pulmonary tuberculosis at a tertiary care center in Uganda: a case series

Chronic Pulmonary Aspergillosis as a Considerable Complication in Post-Tuberculosis Lung Disease

Post-tuberculosis lung disease (PTLD) has only recently been put in the spotlight as a medical entity. Recent data suggest that up to 50% of tuberculosis (TB) patients are left with PTLD-related impairment after completion of TB treatment. The presence of residual cavities in the lung is the largest risk factor for the development of chronic pulmonary aspergillosis (CPA) globally. Diagnosis of CPA is based on four criteria including a typical radiological pattern, evidence of Aspergillus species, exclusion of alternative diagnosis, and a chronic course of disease. In this manuscript, we provide a narrative review on CPA as a serious complication for patients with PTLD.

Re-estimation of the burden of serious fungal diseases in Uganda

Background

It is of utmost importance to monitor any change in the epidemiology of fungal diseases that may arise from a change in the number of the at-risk population or the availability of local data.

Objective

We sought to update the 2015 publication on the incidence and prevalence of serious fungal diseases in Uganda.

Methods

Using the Leading International Fungal Education methodology, we reviewed published data on fungal diseases and drivers of fungal diseases in Uganda. Regional or global data were used where there were no Ugandan data.

Results

With a population of ~45 million, we estimate the annual burden of serious fungal diseases at 4,099,357 cases (about 9%). We estimated the burden of candidiasis as follows: recurrent Candida vaginitis (656,340 cases), oral candidiasis (29,057 cases), and esophageal candidiasis (74,686 cases) in HIV-infected people. Cryptococcal meningitis annual incidence is estimated at 5553 cases, Pneumocystis pneumonia at 4604 cases in adults and 2100 cases in children. For aspergillosis syndromes, invasive aspergillosis annual incidence (3607 cases), chronic pulmonary aspergillosis (26,765 annual cases and 63,574 5-year-period prevalent cases), and prevalence of allergic bronchopulmonary aspergillosis at 75,931 cases, and severe asthma with fungal sensitization at 100,228 cases. Tinea capitis is common with 3,047,989 prevalent cases. For other mycoses, we estimate the annual incidence of histoplasmosis to be 646 cases and mucormycosis at 9 cases.

Conclusion

Serious fungal diseases affect nearly 9% of Ugandans every year. Tuberculosis and HIV remain the most important predisposition to acute fungal infection necessitating accelerated preventive, diagnostic, and therapeutic interventions for the management of these diseases.

The SSS revolution in fungal diagnostics: speed, simplicity and sensitivity

INTRODUCTION

Fungal disease has historically presented a diagnostic challenge due to its often non-specific clinical presentations, relative infrequency and reliance on insensitive and time-intensive fungal culture.

SOURCES OF DATA

We present the recent developments in fungal diagnostics in the fields of serological and molecular diagnosis for the most clinically relevant pathogens; developments that have the potential to revolutionize fungal diagnosis through improvements in speed, simplicity and sensitivity. We have drawn on a body of evidence including recent studies and reviews demonstrating the effectiveness of antigen and antibody detection and polymerase chain reaction (PCR) in patients with and without concurrent human immunodeficiency virus infection.

AREAS OF AGREEMENT

This includes recently developed fungal lateral flow assays, which have a low cost and operator skill requirement that give them great applicability to low-resource settings. Antigen detection for Cryptococcus, Histoplasma and Aspergillus spp. are much more sensitive than culture. PCR for Candida spp., Aspergillus spp., Mucorales and Pneumocystis jirovecii is more sensitive than culture and usually faster.

AREAS OF CONTROVERSY

Effort must be made to utilize recent developments in fungal diagnostics in clinical settings outside of specialist centres and integrate their use into standard medical practice. Given the clinical similarities of the conditions and frequent co-infection, further study is required into the use of serological and molecular fungal tests, particularly in patients being treated for tuberculosis.

GROWING POINTS

Further study is needed to clarify the utility of these tests in low-resource settings confounded by a high prevalence of tuberculosis.

AREAS TIMELY FOR DEVELOPING RESEARCH

The diagnostic utility of these tests may require revision of laboratory work flows, care pathways and clinical and lab coordination, especially for any facility caring for the immunosuppressed, critically ill or those with chronic chest conditions, in whom fungal disease is common and underappreciated.

Overcoming clinical challenges in the management of invasive fungal infections in low- and middle-income countries (LMIC)

INTRODUCTION

The management of invasive fungal infections (IFIs) in low- and middle-income countries (LMIC) is a serious challenge due to limited epidemiology studies, sub-optimal laboratory facilities, gap in antifungal management training and resources. Limited studies highlighted distinctive epidemiology of IFIs in those countries, and difficulty in distinguishing from closely related infections. To overcome the gaps for appropriate management of IFIs, innovative approaches are required.

AREAS COVERED

Extensive literature search and discussion with experts have helped us to summarize the epidemiology, diagnostic and management difficulties in managing IFIs in LMIC, and recommend certain solutions to overcome the challenges.

EXPERT OPINION

The strategies to overcome the challenges in diagnosis may include local epidemiology study, training of healthcare workers, association of fungal infections with already existing budgeted national programs, development and incorporation of point-of-care test (POCT) for prompt diagnosis, simplifying clinical diagnostic criteria suitable for LMIC, judicious use of available expertise, and diagnostic stewardship. For management strategies judicious use of antifungal, partnering with industry for inexpensive antifungal agents, development of LMIC specific guidelines for cost-effective management of IFIs and fungal outbreaks, improvement of infection control practices, advocacy for implementation of WHO recommended antifungal use, and integration of IFIs with public health.

The Fungal and Bacterial Interface in the Respiratory Mycobiome with a Focus on Aspergillus spp

The heterogeneity of the lung microbiome and its alteration are prevalently seen among chronic lung diseases patients. However, studies to date have primarily focused on the bacterial microbiome in the lung rather than fungal composition, which might play an essential role in the mechanisms of several chronic lung diseases. It is now well established that Aspergillus spp. colonies may induce various unfavorable inflammatory responses. Furthermore, bacterial microbiomes such as Pseudomonas aeruginosa provide several mechanisms that inhibit or stimulate Aspergillus spp. life cycles. In this review, we highlighted fungal and bacterial microbiome interactions in the respiratory tract, with a focus on Aspergillus spp.

New estimation of the prevalence of chronic pulmonary aspergillosis (CPA) related to pulmonary TB - a revised burden for India

Background

Chronic pulmonary aspergillosis (CPA) may be confused with, or a coinfection of, pulmonary tuberculosis (PTB), or may manifest itself after completion of antituberculous therapy (ATT).

Methods

Literature searches were conducted on PubMed. The selected studies stated the timing of CPA diagnosis with respect to PTB. The key assumptions for estimating the annual incidence, annual deaths, and 5-year-period prevalence related to CPA were: of the clinically diagnosed PTB patients , 19% of those HIV-negative had CPA and 7% of HIV-positive patients had CPA; the percentage of patients presenting in the first year after PTB diagnosis or developing CPA as ATT finished was 10%; the annual rate of development of CPA from 2-5 years after PTB diagnosis was 1.5%; and the mortality of CPA was 20% in year 1 and 7.5% thereafter to year 5.

Findings

In India, the annual incidence of CPA arising in PTB patients in 2019 was estimated to be 363 601  cases (range 254 521 - 472 682) and 42 766 deaths (range 29  936-55 595) - 10.5% of total PTB deaths. The 5-year-period prevalence of CPA was estimated at   1 575 716 , with an additional 100 715 deaths' total range of deaths 100 436- 186 525) annually.

Interpretation

The revised estimation indicates a substantial unmet need for better diagnosis of CPA as part of a complex PTB-related respiratory morbidity burden.

Serological evidence of chronic pulmonary Aspergillosis in tuberculosis patients in Kenya

BACKGROUND

Pulmonary tuberculosis (PTB) is a significant risk factor for fungal infection. The cavitary lesions post PTB serves as a good reservoir for fungal colonization and subsequent infection. Furthermore, the severe immunosuppression associated with HIV and TB co-infection is another predisposition. The inadequate capacity to investigate and manage fungal infection in PTB patients increases their morbidity and mortality. The study aimed to provide serological evidence of chronic pulmonary aspergillosis (CPA) among PTB patients in Kenya. Towards this, we analysed 234 serum samples from patients presenting with persistent clinical features of PTB infections despite TB treatment in four referral hospitals.

METHODS

This was a cross sectional laboratory based study and patients were recruited following an informed consent. Serological detection of Aspergillus fumigatus IgG was done using enzyme-linked immunosorbent assay (Bordier Affinity Products SA). Sputum samples were subjected to microscopy and standard fungal culture. The isolated fungi were subjected to macro and micro morphological identifications and confirmed by sequence analysis of calmadulin, betatubilin and ITS genes.

RESULTS

Serological evidence of CPA or fungal sensitization was 46(19.7%) and equivocal or borderline was 14(6.0%). Mycological investigations of sputum resulted in 88(38%) positive for fungal culture. Aspergillus spp. accounted for 25(28%) of which A. fumigatus was 13(14.8%), A. niger 8(9.1%), A. terreus, A. flavus, A. candidus and A. clavatus 1 (1.1%) each. This was followed by Penicillium spp. 10 (11.4%), Scedosporium spp. 5 (5.7%) and Rhizopus spp. 3 (3.4%). Among the yeasts; Candida albicans accounted for 18(20.5%) followed by C. glabrata 5(5.7%). Cryptococcus spp. was isolated from 3(3.4%) of the samples while 13(14.8%) were other yeasts.

CONCLUSION

Chronic pulmonary aspergillosis is a significant co-morbidity in PTB patients in Kenya that could be misdiagnosed as relapse or treatment failures in the absence of reliable diagnostic and clinical management algorithm. It could be the cause of persistent clinical symptoms despite TB treatment often misdiagnosed as TB smear/GeneXpert MTB/RIF® negative or relapse. We recommend that all patients with persistent clinical symptoms despite TB treatment should be subjected to fungal investigations before retreatment.

Chronic Pulmonary Aspergillosis is Common among Patients with Presumed Tuberculosis Relapse in Ghana

Chronic pulmonary aspergillosis (CPA) may mimic pulmonary tuberculosis (PTB). The two diseases are clinically indistinguishable and may result in CPA misdiagnosed as PTB or vice versa. Although PTB is largely recognised as a differential diagnosis of CPA and often ruled out prior to CPA diagnosis, the reverse is uncommon. The aim of this study was to determine the proportion of CPA cases among patients being assessed for PTB. A cross-sectional survey was conducted among consecutive patients referred for GeneXpert Mycobacterium tuberculosis test for the diagnosis of PTB at the Korle-Bu Teaching Hospital, Accra, Ghana. Patients’ demographics, clinical and socioeconomic details were obtained using a structured questionnaire. Blood was collected for Aspergillus and HIV serology, and sputum samples obtained for Aspergillus culture. Chest radiograph was obtained, and computed tomography scan was also done for patients with positive Aspergillus serology or cavitation. CPA was defined using an algorithm developed by the Global Action for Fungal Infections (GAFFI) international expert panel. A total of 154 patients were included in the analysis, of whom 134 (87%) did not have a prior PTB diagnosis. There were 41 (26.6%) GeneXpert positive cases. CPA prevalence was 9.7% overall, but 50% in patients with a prior history of PTB and 3.7% in those without previous PTB. Although CPA is rarely considered as a differential diagnosis of PTB in Ghana, our findings show that CPA may affect half of patients being assessed for PTB relapse. Efforts to diagnose CPA should be prioritised in this patient group.

Pulmonary and Extrapulmonary Manifestations of Fungal Infections Misdiagnosed as Tuberculosis: The Need for Prompt Diagnosis and Management

Fungal infections commonly present with myriad symptoms that mimic other clinical entities, notable amongst which is tuberculosis. Besides histoplasmosis and chronic pulmonary aspergillosis, which can mimic TB, this review has identified several other fungal infections which also do. A total of 80 individual cases misdiagnosed as TB are highlighted: aspergillosis (n = 18, 22.5%), histoplasmosis (n = 16, 20%), blastomycosis (n = 14, 17.5%), cryptococcosis (n = 11, 13.8%), talaromycosis (n = 7, 8.8%), coccidioidomycosis (n = 5, 6.3%), mucormycosis (n = 4, 5%), sporotrichosis (n = 3, 3.8%), phaeohyphomycosis (n = 1, 1.3%) and chromoblastomycosis (n = 1, 1.3%). Case series from India and Pakistan reported over 100 cases of chronic and allergic bronchopulmonary aspergillosis had received anti-TB therapy before the correct diagnosis was made. Forty-five cases (56.3%) had favorable outcomes, and 25 (33.8%) died, outcome was unclear in the remainder. Seventeen (21.3%) cases were infected with human immunodeficiency virus (HIV). Diagnostic modalities were histopathology (n = 46, 57.5%), culture (n = 42, 52.5%), serology (n = 18, 22.5%), cytology (n = 2, 2.5%), gene sequencing (n = 5, 6.3%) and microscopy (n = 10, 12.5%) including Gram stain, India ink preparation, bone marrow smear and KOH mount. We conclude that the above fungal infections should always be considered or ruled out whenever a patient presents with symptoms suggestive of tuberculosis which is unconfirmed thereby reducing prolonged hospital stay and mortalities associated with a delayed or incorrect diagnosis of fungal infections.

Chronic pulmonary aspergillosis in patients with active pulmonary tuberculosis with persisting symptoms in Uganda

BACKGROUND

The occurrence of chronic pulmonary aspergillosis (CPA) among drug sensitive pulmonary tuberculosis (PTB) patients on optimal therapy with persistent symptoms was investigated.

METHODS

We consecutively enrolled participants with PTB with persistent pulmonary symptoms after 2 months of anti-TB treatment at Mulago Hospital, Kampala, Uganda between July 2020, and June 2021. CPA was defined as a positive Aspergillus-specific IgG/IgM immunochromatographic test (ICT), a cavity with or without a fungal ball on chest x-ray (CXR), and compatible symptoms >3 months.

RESULTS

We enrolled 162 participants (median age 30 years; IQR: 25 - 40), 97 (59.9%) were male, 48 (29.6%) were HIV-infected, and 15 (9.3%) had prior PTB. Thirty-eight (23.4%) sputum samples grew A. niger and 13 (8.0%) A. fumigatus species complexes. Six (3.7%) participants had intra-cavitary fungal balls, and 52 (32.1%) had cavities. Overall, 32 (19.8%) participants had CPA. CPA was associated with prior PTB (adjusted odds ratio (aOR): 6.61, 95% CI: 1.85 - 23.9, p=0.004), and far advanced CXR changes (aOR: 4.26, 95%CI: 1.72 - 10.52, p=0.002). The Aspergillus IgG/IgM ICT was positive in 10 (31.3%) participants with CPA.

CONCLUSIONS

CPA may cause persistent respiratory symptoms in up to one-fifth of patients after intensive treatment for PTB. The Aspergillus IgG/IgM ICT positivity rate was very low and may not be used alone for the diagnosis of CPA in Uganda.

Chronic Pulmonary Aspergillosis: A Brief Review

Chronic Pulmonary Aspergillosis (CPA) is a destructive pulmonary disease caused by a fungal infection, affecting mainly individuals with prior or concurrent pulmonary conditions. It has a global prevalence of 42 per 100,000 population, but in the US and Europe, prevalence is less than 1 per 100,000. The clinical definition of CPA is based on various factors accounting for comorbidities, clinical presentation, and duration. It may be categorized into five subtypes that the disease may evolve between over time. Based on global consensus covering the spectrum of low-resource to high-resource settings, diagnosis is a multi-factorial process that involves a combination of clinical presentation persisting over 3 months, radiological findings, positive culture growth, and serological tests. CPA remains underdiagnosed due to a lack of awareness and is often misdiagnosed due to the comorbidities present. Treatment options are limited due to a lack of research. Furthermore, associated comorbidities and drug interactions further complicate treatment plans. Follow-up throughout treatment should be based on understanding the predictors of mortality. Identification of potential relapse or resistance to antifungal therapy is crucial to limit the low long-term survival rate. Awareness surrounding this devastating disease needs to be raised further to enable earlier identification, improve understanding of patient factors associated with prognosis, and the future potential for targeted therapies. This review aims to raise awareness of this rare condition among practitioners, by providing an overview of common risk factors influencing the prevalence and incidence of the disease. We further discuss current approaches and recent advancements in CPA diagnosis and treatment.

Mapping of Chronic Pulmonary Aspergillosis in Africa

Africa has a high burden of tuberculosis, which is the most important risk factor for chronic pulmonary aspergillosis (CPA). Our goal was to systematically evaluate the burden of CPA in Africa and map it by country. We conducted an extensive literature search for publications on CPA in Africa using the online databases. We reviewed a total of 41 studies published between 1976 and 2021, including a total of 1247 CPA cases from 14 African countries. Most of the cases came from Morocco (n = 764, 62.3%), followed by South Africa (n = 122, 9.9%) and Senegal (n = 99, 8.1%). Seventeen (41.5%) studies were retrospective, 12 (29.3%) were case reports, 5 case series (12.2%), 5 prospective cohorts, and 2 cross-sectional studies. The majority of the cases (67.1%, n = 645) were diagnosed in men, with a median age of 41 years (interquartile range: 36–45). Active/previously treated pulmonary tuberculosis (n = 764, 61.3%), human immunodeficiency virus infection (n = 29, 2.3%), diabetes mellitus (n = 19, 1.5%), and chronic obstructive pulmonary disease (n = 10, 0.8%) were the common co-morbidities. Haemoptysis was the most frequent presenting symptom, reported in up to 717 (57%) cases. Smoking (n = 69, 5.5%), recurrent lung infections (n = 41, 3%) and bronchorrhea (n = 33, 3%) were noted. This study confirms that CPA is common in Africa, with pulmonary tuberculosis being the most important risk factor.

Surgical management of chronic pulmonary aspergillosis in Africa: A systematic review of 891 cases

Chronic pulmonary aspergillosis (CPA) is an emerging fungal infectious disease of public health importance. We conducted a systematic review of studies reporting the outcomes of patients with CPA managed surgically in Africa. A search of Medline, Embase, Web of Science, Google Scholar and African Journals Online was conducted to identify studies indexed from inception to June 2021 that examined surgical management of CPA in Africa. All articles that presented primary data, including case reports and case series, were included. We excluded review articles. A total of 891 cases (557 males (62.5%), mean age 39.3 years) extracted from 27 eligible studies published between 1976 and 2020 from 11 African countries were included. Morocco (524, 59%) and Senegal (99, 11%) contributed the majority of cases. Active or previous pulmonary tuberculosis was reported in 677 (76.0%) cases. Haemoptysis was reported in 682 (76.5%) cases. Lobectomy (either unilateral or bilateral, n = 493, 55.3%), pneumonectomy (n = 154, 17.3%) and segmentectomy (n = 117, 13.1%) were the most frequently performed surgical procedures. Thirty (4.9%) cases from South Africa received bronchial artery embolisation. Empyema (n = 59, 27.4%), significant haemorrhage (n = 38, 173.7%), incomplete lung expansion (n = 26, 12.1%) and prolonged air leak (n = 24, 11.2%) were the most frequent complications. Overall, 45 (5.1%) patients died. The causes of death included respiratory failure (n = 14), bacterial superinfection/sepsis (n = 10), severe haemorrhage (n = 5), cardiopulmonary arrest (n = 3) and complications of chronic obstructive pulmonary disease (n = 3). The cause of death was either unknown or unspecified in 9 cases. We conclude that surgical treatment had very low mortality rates and maybe considered as first-line management option in centres with experience and expertise in Africa.