Surgical Management of Hidradenitis Suppurativa.

Hidradenitis suppurativa (HS) is a chronic, relapsing inflammatory disease of the skin, characterized by recurrent draining sinuses and abscesses, predominantly in skin folds carrying terminal hairs and apocrine glands. Treatment for this debilitating disease has been medical management with antibiotics and immune modulators. With the advent of better reconstructive surgical techniques, the role of surgery in the treatment of HS has expanded, from being a last resort to a modality that is deployed earlier. Larger defects can be more easily reconstructed, allowing for a more radical excision of diseased areas. Locoregional flaps, perforator flaps, and propeller flaps that use the fasciocutaneous tissue allow reconstruction of defects with similar tissue, and provide better cosmetic and functional outcomes. They are easy to execute and can be performed even in resource-poor settings with concurrent use of immune modulators and postoperative antibiotics. Hidradenitis can be successfully treated with surgery in early stages as well as severe disease, due to the advances in understanding disease behavior, multidisciplinary care, and advanced reconstructive techniques. Coupled with a multidisciplinary care team, surgery offers a durable, lasting cure for HS, significantly reducing disease morbidity.

Actinomyces-infected bronchopulmonary sequestration: An uncommon pathogen in a rare anomaly.

Bronchopulmonary sequestration, a rare congenital anomaly, involves a nonfunctioning lung tissue mass supplied by anomalous vessels. It is rarely infected by Actinomyces, further complicating the clinical presentation, with limited reported cases. This case highlights the distinctive clinical aspects, diagnostic challenges, and successful management strategies of such a rare clinical entity.

Prepubertal Female Bartholin's Gland Abscess: A Comprehensive Case Report Study.

Introduction: Bartholin's gland abscesses are rare in pediatric patients, with limited documented cases. This case report aims to contribute valuable insights into managing this uncommon condition in children. Methods: A thorough examination and diagnostic workup were conducted on a 4-month-old female infant presenting with labial swelling. Clinical assessment strongly suggested the presence of a Bartholin's gland abscess. A culture of purulent discharge revealed the presence of Escherichia coli and Gram-negative Klebsiella pneumoniae. Antibiotic susceptibility testing guided the choice of treatment. Case Presentation. Despite initial treatment with oral antibiotics and sitz baths, there was limited therapeutic response. Close surveillance under the guidance of a pediatric surgeon continued for two months. Subsequently, surgical excision of the Bartholin gland was performed, and the specimen was sent for pathological examination. Results: Pathological analysis revealed signs of ulceration and granulation tissue, indicative of a mixed inflammatory response. An eight-month follow-up demonstrated marked improvement and overall well-being in the patient. Conclusion: This case report underscores the importance of considering Bartholin's gland abscess in diagnosing labial swelling in pediatric patients. The successful outcome achieved through surgical excision and appropriate antibiotic therapy provides valuable insights for potential treatment approaches in similar cases. Continued research and comprehensive studies are essential for establishing optimal treatment protocols for this patient demographic.

Biphasic Peritoneal Mesothelioma Is a Rare Tumor and a Diagnostic Challenge: A Case Report.

Malignant peritoneal mesothelioma (MPM) is a rare subtype of mesothelioma. There are three main histological subtypes of mesothelioma: epithelioid, sarcomatoid, and biphasic (mixed). Risk factors include asbestos exposure, previous radiation, and some germline mutations. Treatment includes surgical resection of amenable tumors or cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. We present a 34-year-old male who presented with weight loss, night sweats, and pleuritic chest pain and was found to have ascites with peritoneal nodularity on abdominal imaging. He had a history of tuberculosis contact, but no history of asbestos exposure. After a long challenging and interesting diagnostic process, he was subsequently diagnosed with biphasic MPM. The diagnostic challenge stems from not only the rarity of the tumor but also from the absence of risk factors, the unavailability of some special laboratory investigations, in addition to the potentially misleading effect of tuberculosis exposure history, a top differential diagnosis in the case. This is a case report of a really challenging and totally unexpected diagnosis of biphasic peritoneal mesothelioma in a patient with tuberculosis exposure, constitutional symptoms, but no history of asbestos exposure. It highlights the diagnostic process as well as the importance of early diagnosis to improve the overall survival of such malignancies.

A Rare Presentation of Artery of Percheron Infarct: A Case Report.

The artery of Percheron (AOP), a variation of the thalamic vasculature, supplies both the thalamus and the midbrain. An infarct in this area is characterized by wide neurological abnormalities, the most common of which are altered mental state, decreased degree of consciousness, and memory impairment. AOP infarcts tend to be missed during the initial computed tomography (CT) scan. The number of reports on AOP infarction has been increasing, highlighting the range of clinical presentations and challenges that clinicians can face. This case study discusses a 58-year-old male patient who was diagnosed with stroke in AOP territory without any clear neurological symptoms, and it serves as a model for patients with similar conditions.

Patient perspectives on recall period and response options in patient-reported outcome measures for chronic rhinosinusitis symptomatology: An international multi-centered study.

BACKGROUND: Existing patient-reported outcome measures (PROMs) for chronic rhinosinusitis (CRS) use a variety of recall periods and response scales to assess CRS symptom burden. Global perspectives of CRS patients regarding optimal recall periods and response scales for CRS PROMs are unknown. METHODS: This was a multi-center, cross-sectional study recruiting 461 CRS patients from sites across the United States, Saudi Arabia, New Zealand, and Austria. Participants chose which CRS symptom recall period (1 day, 2 weeks, 1 month, >1 month) was most reflective of their current disease state and upon which to best base treatment recommendations (including surgery). Participants also chose which of six response scales (one visual analogue scale and five Likert scales ranging from four to eight items) was easiest to use, understand, and preferred. RESULTS: A plurality of participants (40.0%) felt their CRS symptoms' current state was best reflected by a 1-month recall period. However, most patients (56.9%) preferred treatment recommendations to be determined by symptoms experienced over a >1 month period. The four- and five-item Likert scales were the easiest to understand (26.0% and 25.4%, respectively) and use (23.4% and 26.7%, respectively). The five-item (26.4% rating it most preferred and 70.9% rating it preferred) and four-item Likert (22.3% rating it most preferred and 56.4% rating it preferred) response scales were most preferred. CONCLUSION: Future PROMs for CRS should consider assessment of symptoms over a 1-month period and use a four- or five-item Likert response scale to reflect global patient preferences. These findings also inform interpretation of current CRS PROMs.

Machine learning for modeling N2O emissions from wastewater treatment plants: Aligning model performance, complexity, and interpretability.

Nitrous oxide (N2O) emissions may account for up to 80 % of a wastewater treatment plant's (WWTP) total carbon footprint. Given the complexity of the pathways involved, estimating N2O emissions through mechanistic models still often fails to precisely depict process dynamics. Alternatively, data-driven methods for predicting N2O emissions hold substantial potential. However, so far, a comprehensive approach is still overlooked, impeding the advancement of full-scale application. Therefore, this study develops a comprehensive approach for using machine learning to perform online process modeling of N2O emissions. The approach is tested on a long-term N2O emission dataset from a full-scale WWTP. Uniquely, the proposed approach emphasizes not just model accuracy, but it also considers model complexity, computational speed, and interpretability, equipping operators with the insights needed for informed corrective actions. Algorithms with varying levels of complexity and interpretability including k-Nearest Neighbors (kNN), decision trees, ensemble learning models, and deep neural networks (DNN) were considered. Furthermore, a parametric multivariate outlier removal method was adjusted to account for data statistical distributions, significantly reducing data loss. By employing an effective feature selection methodology, a trade-off between data acquisition, model performance, and complexity was found, reducing the number of features by 40 % and decreasing data collection cost, model complexity and computational burden without significant effect on modeling accuracy. The best performing models are kNN (R2 = 0.88), AdaBoost (R2 = 0.94), and DNN (R2 = 0.90). Feature importance of models was analyzed and compared with process knowledge to test interpretability, guiding N2O mitigation decisions.

The utility of testing erythropoietin level in polycythemia diagnosis.

OBJECTIVES: Polycythemia vera (PV) is classically thought to be associated with low erythropoietin (EPO) levels. Here, we present a review of the utility of using EPO levels in diagnosing polycythemia. METHODS: We conducted a systematic literature review of the Medline data through Pubmed and Google Scholar. We included the articles which described confirmed PV associated with elevated EPO level. Our search strategy included the following terms in Pubmed (((polycythemia vera[MeSH Terms]) OR (jak2 protein tyrosine kinase[MeSH Terms])) OR (Myeloproliferative Disorders[MeSH Terms])) AND (Erythropoietin[MeSH Terms]), and 'polycythemia vera with erythropoietin' in Google Scholar. RESULTS: Our research yielded four cases of PV with elevated EPO levels. The most common symptom was a headache. Thrombotic phenomena happened in a single case in the form of Budd-Chiari syndrome. The mean Hb level was 20.2 gm/dl, and the EPO level was 213 mlU/mL. DISCUSSION: Although PV is usually associated with low EPO levels, high levels do not exclude this diagnosis. Workup should include testing for JAK2 mutation and bone marrow biopsy in the presence of suggestive signs and symptoms. Novel biomarkers are also being proposed to aid in the diagnosis. CONCLUSION: Although elevated EPO levels suggest secondary causes of polycythemia, cases where elevated EPO levels were associated with an underlying PV are reported in the literature, and we have summarized a review of them. Workup for polycythemia should include JAK2 mutation testing if signs and symptoms suggest PV even if EPO is elevated.

STIMA: Submucosal Temporary Inferior Maxillary Antrostomy: A Cadaveric Controlled Study of a Modification of the Conventional Antrostomy.

Introduction: Inferior meatal antrostomy (IMA) is a safe and easy approach to the maxillary sinus. However, studies have shown disadvantages of conventional IMA, such as disruption of mucociliary transport and injury of the nasolacrimal duct (NLD). Endoscopic middle meatal antrostomy (MMA) has become the standard of care for addressing various maxillary pathologies. It is more functional and physiological but offers limited exposure to certain areas of the maxillary sinus, such as the prelacrimal recess, alveolar recess, and zygomatic recess. We proposed submucosal temporary inferior maxillary antrostomy (STIMA) to improve visualization and accessibility to such difficult-to-access locations. Objectives: To describe our proposed modification, to compare the degree of visualization and ease of accessibility between MMA and STIMA. Methods: This is a descriptive cadaveric study. It was performed on 4 fresh frozen human cadavers, and 8 maxillary sinuses were used to achieve the study's objectives. Different angled rigid nasal endoscopes and suction tubes were used to score the degree of visualization and ease of accessibility between the MMA and STIMA. Result: We demonstrated the superiority of the STIMA over the MMA in the degree of visualization and ease of accessibility in these difficult-to-access locations (P-value was significant, <.05). We did not encounter orbital injury or injury to the NLD in our specimens. Conclusion: STIMA is a relatively easy and safe modification of conventional IMA. It improves the degree of visualization and ease of accessibility to difficult-to-access maxillary sinus locations without the potential complications of conventional IMA.

Complications of endoscopic sinus surgery for chronic rhinosinusitis in a tertiary care teaching hospital in Saudi Arabia.

OBJECTIVES: To aimed to determine the incidence of complications of endoscopic sinus surgery (ESS) and to investigate the factors associated with the occurrence of complications. METHODS: In this retrospective study, we reviewed the medical records of all patients who had undergone ESS at King Saud University Medical City (KSUMC) between January 2015 and March 2022. Patients who underwent ESS for complicated acute sinusitis, sinonasal malignancy, and cerebrospinal fluid leak repair, and those who underwent extended ESS for indications other than chronic rhinosinusitis were excluded. This study was approved by the KSUMC Institutional Review Board. RESULTS: We included 1395 patients, 3 of whom had major complications and 28 had minor complications, resulting in an overall major complication rate of 0.2% and a minor complication rate of 2%. The most common major complication was orbital hematoma, and the most common minor complication was synechia. Moreover, the duration of surgery and laterality increased the risk of complications, whereas the use of image guidance had no effect. CONCLUSION: The ESS is a safe procedure. The operative start time and laterality were associated with an increased risk of complications and warrant further investigation.

Masculinizing chest wall gender-affirming surgery: Clinical outcomes of 73 subcutaneous mastectomies using the double-incision and semicircular incision techniques.

Masculinizing chest wall gender-affirming surgery is an important element in the treatment of gender dysphoria. In this study, we report an institutional series of subcutaneous mastectomies and aim to identify the risk factors for major complications and revision surgery. A retrospective review of consecutive patients who underwent primary masculinizing top surgery via subcutaneous mastectomy at our institution through July 2021 was performed. Demographics and clinical characteristics were recorded as well as major complications and revision surgeries. Time-to-event analyses were performed to assess predictors of major complications and revision surgery. Seventy-three consecutive patients (146 breasts) were included. The mean age and the mean body mass index were 25.2 ± 7 years and 27.6 ± 6.5 kg/m2, respectively. The mean follow-up time was 7.9 ± 7.5 months. None of the patients had a history of chest wall radiation or breast surgery. Double incision with free nipple grafting was the most common technique (n = 130, 89%), followed by periareolar semicircular incision (n = 16, 11%). The mean resection weight was 524.7 ± 377.7 g. Concomitant suction-assisted lipectomy was performed in 48 (32.9%) cases. The rate of major complications was 2.7%. Revision surgery was performed in 8 (5.4%) cases. Concomitant liposuction was significantly associated with a lower rate of revision surgery (p = 0.026). Masculinizing chest wall gender-affirming surgery is a safe procedure with a low rate of revision. Concomitant liposuction significantly reduced the need of revision surgery. Future studies utilizing patient-reported outcomes are still required to better assess the success of this procedure.

Immune Thrombocytopenia Relapse in Patients Who Received mRNA COVID-19 Vaccines.

Background: Immune thrombocytopenia (ITP) is a blood disorder in which antibodies coating platelets cause platelet destruction in the spleen with a resultant low platelet count and an increased tendency for bleeding. Coronavirus disease 2019 (COVID-19) is an illness caused by SARS-CoV-2. Though pneumonia and respiratory failure are major causes of morbidity and mortality, multisystemic complications were identified, including hematological ones. Several ITP relapse cases post-mRNA SARS-CoV-2 vaccines have been reported, and different pathophysiological theories have been proposed. Purpose: The objective of this study is to identify the causal relationship between mRNA COVID-19 vaccines and ITP relapse, to highlight the longer-term effect of these vaccines on the platelet count more than 6 months after receiving the vaccine, and to identify if there is a statistical difference between Comirnaty and Spikevax vaccines on ITP relapse rate. Patients and Methods: In this retrospective study, 67 patients with known ITP were followed before and after receiving the mRNA COVID-19 vaccine. The follow-up parameters included platelet counts when available and bleeding symptoms. All patients were adults over 18 years old, with no other identified causes of thrombocytopenia. Forty-seven patients received the Comirnaty vaccine, and 20 patients received the Spikevax vaccine. Results: Data analysis showed 6% ITP relapse in the first 3 months, and a 10% relapse rate 3-6 months after receiving one of the mRNA COVID-19 vaccines, with no statically significant difference between the two vaccines. Conclusion: mRNA COVID-19 vaccines increase the risk of ITP relapse and can lead to a prolonged reduction in platelet count in a proportion of ITP patients, with no statistically significant difference between Comirnaty and Spikevax vaccines.

Neisseria elongata-mediated peritonitis in an end-stage renal disease patient on automated peritoneal dialysis: a case report and literature review.

Peritoneal dialysis (PD) can result in peritonitis, which frequently causes severe and near-fatal clinical implications if left untreated. Usually, gram-positive bacteria are the most common organisms involved. Uncommonly recognized as the cause of peritonitis in PD patients, Neisseria elongata is a gram-negative nasal and oropharyngeal normal flora organism. Case presentation: We report a rare case of a 29-year-old man who had received automated PD for 6 years and had N. elongata peritonitis. Discussion: Several case reports of Neisseria-related peritonitis may point to the potential pathogenicity of such organisms and suggest that many cases of culture-negative peritonitis may have been misdiagnosed. Poor nutrition and chronic kidney disease have been suggested as potential risk factors for N. elongata peritonitis, both of which are present in our patient. With appropriate antibiotic use, most of the cases respond well to empirical treatment. Conclusion: Although rare, N. elongata can lead to PD catheter. peritonitis that, in some cases, require changing to hemodialysis.

Mechanistic assessment reveals the significance of HRT and MLSS concentration in balancing carbon diversion and removal in the A-stage process.

Nowadays, the shift toward energy and resource-efficient wastewater treatment plants (WWTPs) has become a necessity rather than a choice. For this purpose, there has been a restored interest in replacing the typical energy and resource-extensive activated sludge process with the two-stage Adsorption/bio-oxidation (A/B) configuration. In the A/B configuration, the role of the A-stage process is to maximize organics diversion to the solids stream and control the following B-stage's influent to allow for the attainment of tangible energy savings. Operating at very short retention times and high loading rates, the influence of the operational conditions on the A-stage process become more tangible than typical activated sludge. Nonetheless, there is very limited understanding of the influence of operational parameters on the A-stage process. Moreover, no studies in the literature have explored the influence of any operational/design parameters on the Alternating Activated Adsorption (AAA) technology which is a novel A-stage variant. Hence, this article mechanistically investigates the independent effect of different operational parameters on the AAA technology. It was inferred that solids retention time (SRT) shall remain below 1 day to allow for energy savings up to 45% and redirecting up to 46% of the influent's COD to the recovery streams. In the meantime, the hydraulic retention time (HRT) can be increased up to 4 h to remove up to 75% of the influent's COD with only 19% decline of the system's COD redirection ability. Moreover, it was observed that the high biomass concentration (above 3000 mg/L) amplified the effect of the sludge poor settleability either due to pin floc settling or high SVI30 which resulted in COD removal below 60%. Meanwhile, the concentration of the extracellular polymeric substances (EPS) was not found to be influenced or to influence process performance. The findings of this study can be employed to formulate an integrative operational approach in which different operational parameters are incorporated to better control the A-stage process and achieve complex objectives.

Neisseria elongata -mediated peritonitis in an end-stage renal disease patient on automated peritoneal dialysis, A case report and literature review.

Introduction: Peritoneal dialysis (PD) can result in peritonitis, which frequently causes severe and near-fatal clinical implications if left untreated. Usually, Gram-positive bacteria are the most common organisms involved. Uncommonly recognized as the cause of peritonitis in PD patients, Neisseria Elongata is a gram-negative nasal and oropharyngeal normal flora organism. Case presentation: We report a rare case of a 29-year-old man who had received automated peritoneal dialysis for six years and had Neisseria Elongata peritonitis. Discussion: Several case Reports of niseria-related peritonitis may point to the potential pathogenicity of such organisms and suggest that many cases of culture-negative peritonitis may have been misdiagnosed. Poor nutrition and chronic kidney disease have been suggested as potential risk factors for Neisseria elongata peritonitis [8], both of which are present in our patient. With appropriate antibiotic use, most of the cases respond well to empirical treatment. Conclusion: Although rare, Neisseria Elongata can lead to Peritoneal Dialysis catheter Peritonitis that, in some cases, require changing to hemodialysis.

Turkish Stock Market from Pandemic to Russian Invasion, Evidence from Developed Machine Learning Algorithm.

In recent time, the two significant events; Coronavirus epidemic and Russian invasion are effecting all over the world in various aspects; healthily, economically, environmentally, and socially, etc. The first event has brought uncertainties to the economic situation in most countries based on the epidemic transmission. In addition to that, on 24th February 2022 the Russian invasion of Ukraine affected negatively almost all stock markets all over the world, but the effects are heterogeneous across countries according to their economic-political relationship or neighbourhood, etc. Due to that, the stock market price in Turkey has been affected dramatically over that period. This empirical study is the first attempts to explore the impact of Coronavirus epidemic and Russian invasion on the stock market index XU100 in Turkey by applying the developed statistical method namely elastic-net regression based on empirical mode decomposition which can precisely tackle the nonstationary and nonlinearity data. Then we performed the robustness check by applying a nonlinear techniques Markov switching regression. The data are collected from the beginning of the epidemic in Turkey from March 11, 2020 until May 31, 2022. The finding reveals that there is significant effect of the Coronavirus spreading on the Turkish stock market index, particularly during the first wave. Then after the Russian Invasion the XU100 index is effected more negatively. As the credit default swap and TL reference interest rate have a negative impact but the foreigner exchange rate has a positive significant impact on the XU100 index, and it varies according to the period of short term and long term. Moreover, the results obtained by using the robustness check shows a robust and consistent finding. In conclusion, understanding the impact of Coronavirus pandemic and Russian invasion on the Turkish stock market can provide important implications for investors, financial sectors, and policymakers.

Nasoseptal flap and rigid reconstruction in endoscopic endonasal skull base surgeries: The longitudinal experience of a single center.

BACKGROUND: Recently, endoscopic endonasal approaches (EEA) have been used for skull base defect reconstruction surgeries. The nasoseptal flap (NSF), a vascular pedicled flap, was introduced to decrease postoperative cerebrospinal fluid (CSF) leakage. PURPOSES: This study aimed to outline the authors' institutional experience using NSF and rigid implants in anterior skull base defect reconstruction surgeries following EEA. DESIGN: A retrospective cohort review of patients who underwent NSF reconstruction following EEA in the Otorhinolaryngology and Neurosurgery Departments at King Saud University Medical City, Riyadh, Saudi Arabia, from January 2015 to May 2021, divided into 2 time periods according to the reconstruction technique. RESULT: Out of the 106 patients who underwent EEA, 77 underwent NSF reconstruction. The majority had expanded EEA (94.8%). The mean age was 40.21 ± 17.7 years, and the female gender represented 61% of the sample. More than half of the sample underwent right NSF (57.1%). Meningioma was the most common diagnosis (45.5%). The clivus was the most frequent site of lesions (23.4%). The overall rate of postoperative CSF leakage and lumbar drainage (LD) insertion was 15.6% and 51.9%, respectively. The duration of LD was a median of four days. The overall failure rate was 13%, declining from 20% in the first period to 5.4% in the second period. Rigid implants were used significantly more in the first period than in the second period (67.5% versus 16.2%, P < 0.001). Meningitis, the highest postoperative complication, was reported in 6 patients (7.8%). One patient died three weeks postoperatively after massive nasal bleeding. No significant difference was found between either side of the NFS regarding the CSF leakage and failure rate. CONCLUSION: In the authors' experience, there has been an overt decline in failure rates and complications of EEA over the last three years due to increased experience among surgeons and a standardization of reconstruction techniques. Minimal reconstruction may provide satisfactory results by decreasing the use of rigid implants. An endoscopic endonasal approach with an NSF for anterior skull base defect reconstruction is considered a safe procedure with no significant difference between the sides of the flap.

Efficacy of Tranexamic Acid in Reducing Seroma and Hematoma Formation Following Reduction Mammaplasty.

BACKGROUND: Tranexamic acid (TXA) has gained increasing recognition as a valuable pharmacologic agent within plastic surgery. OBJECTIVES: The aim of this study was to investigate the value and safety profile of both intravenous and topically administered TXA in the setting of bilateral reduction mammaplasty. METHODS: A retrospective review was performed to identify consecutive patients who underwent bilateral reduction mammaplasty for symptomatic macromastia (January 2016-July 2021). Pertinent preoperative, intraoperative, and postoperative details were collected/reviewed. Primary outcome measures included hematoma requiring surgical evacuation and clinically significant/symptomatic seroma formation mandating percutaneous aspiration. Patients taking anticoagulation/antiplatelet medication or those with a history of thromboembolic diseases were excluded. Patients who had received TXA were compared to a historical control group who did not receive TXA within the same consecutive cohort. RESULTS: A total of 385 consecutive patients (770 breasts) were included. TXA was used in 514 (66.8%) cases (topical, 318 [61.9%]; intravenous, 170 [33.1%]; intravenous and topical, 26 [5.1%]). Neither seroma nor hematoma were impacted/reduced with TXA (P > 0.05). Increased age (hazards ratio, 1.06 per 1-year increase; 95% CI, 1.004-1.118) significantly increased the risk of hematoma (P = 0.032). The use of drains significantly decreased the risk of seroma (P < 0.0001). Increased BMI increased the risk of seroma (hazards ratio, 1.16 per 1-kg/m2 increase; 95% CI, 1.06-1.26; P = 0.0013). The use of TXA did not impact drain duration. CONCLUSIONS: This study, the largest to date on the use of IV and topical TXA, did not find any reduction in risk when using TXA in breast reduction surgery.

An alternative A-stage process - Investigating the novel alternating activated adsorption (AAA) system for carbon management under different wastewater strengths.

The interest in the A-stage of the adsorption/bio-oxidation (A/B) process has considerably increased due to its capacity of carbon redirection to the solids stream. Induced by its flexible and compact design, the Alternating Activated Adsorption (AAA) was recently implemented in full-scale as an alternative A-stage system. However, the literature on such a system is scarce. In this article for the first time, the performance of the novel AAA system is evaluated. Two lab-scale AAA systems were operated as a primary settler replacement (AAA-1) or to complement the primary settler (AAA-2). Systems were assessed in terms of process control, effluent quality and carbon diversion. As settling and aeration are performed in the same reactor, AAA maintained high MLSS (2121 ± 293 mg/L for AAA-1 and 806 ± 116 mg/L for AAA-2) compared to the literature at such a very low aerobic SRT (<6 h). Regardless wastewater strength, AAA attains low oxidation (16-17%) owing to the oxygen supply pattern and short aerobic SRT. Moreover, AAA-1 showed high COD removal efficiency for soluble (67 ± 8%) and particulates (62 ± 14%) as well as COD redirection (47 ± 7%). In addition, it is demonstrated that the simultaneous bottom feeding and top discharging regime adds unique capacity for particulates capture in AAA. On the other hand, low particulates removal and total carbon redirection were observed in the AAA-2. Yet, the overall removal efficiencies are comparable with the literature. It can be concluded that, with further optimizations, AAA system has the potential to outcompete other A-stage systems. As such, sludge settleability is found to be challenging when treating low strength wastewater.